51565415 has 16 divisors (see below), whose sum is σ = 67667616. Its totient is φ = 37411200.

The previous prime is 51565391. The next prime is 51565427. The reversal of 51565415 is 51456515.

51565415 = 475² + 476² + ... + 639².

It is not a de Polignac number, because 51565415 - 2¹² = 51561319 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28889 + ... + 30621.

It is an arithmetic number, because the mean of its divisors is an integer number (4229226).

Almost surely, 2^51565415 is an apocalyptic number.

51565415 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51565415 is a deficient number, since it is larger than the sum of its proper divisors (16102201).

51565415 is a wasteful number, since it uses less digits than its factorization.

51565415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2290.

The product of its digits is 15000, while the sum is 32.

The square root of 51565415 is about 7180.9062798508. The cubic root of 51565415 is about 372.2084020347.

Subtracting from 51565415 its reverse (51456515), we obtain a square (108900 = 330²).

The spelling of 51565415 in words is "fifty-one million, five hundred sixty-five thousand, four hundred fifteen".