what is the similarity between 77 and 15?

Answer 1

They're both the product of 2 consecutive primes:
15 = 3*5
77 = 7*11
and (3,5,7,11) are consecutive primes.

Answer 2

77 = 46 + 31

15 = 46 - 31

Answer 3

They both are the fist number in a Ruth-Aaron pair

Seventy-seven is the sum of three squares, 42 + 52 + 62, as well as the sum of the first eight prime numbers.

77 and 78 form a Ruth-Aaron pair under the second definition in which repeated prime factors are counted as often as they occur.

It is possible for a sudoku puzzle to have as many as 77 givens yet lack a unique solution.

Fifteen is a triangular number and a hexagonal number, a pentatope number, and the 4th Bell number. Fifteen is the double factorial of 5. It is a composite number; its proper divisors being 1, 3 and 5. With only two exceptions, all prime quadruplets enclose a multiple of 15, with 15 itself being enclosed by the quadruplet (11, 13, 17, 19). 15 is also the number of supersingular primes.

15 and 16 form a Ruth-Aaron pair under the second definition in which repeated prime factors are counted as often as they occur.

Fifteen is the magic constant of the unique order-3 normal magic square:

15 is the smallest number that can be factorized using Shor's quantum algorithm.

There are 15 solutions to Znám's problem of length 7.

15 is a repdigit in binary (1111). In hexadecimal, as well as all higher bases, fifteen is represented as F.

Answer 4

77 have 4 factors 1,7,11,77

1*77=77
7*11=77


15 have 4 factors 1,3,5,15

1*15=15
3*5=15

The similarity is both has 4 factors

Answer 5

they are both involved with the figures 46 and 31...both 2 digits

Answer 6

Both are two-digit numbers. Both are odd.

Answer 7

They are both odd numbers