51565565616 has 40 divisors (see below), whose sum is σ = 133297234800. Its totient is φ = 17177400576.

The previous prime is 51565565609. The next prime is 51565565629. The reversal of 51565565616 is 61656556515.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 272415 + ... + 421118.

It is an arithmetic number, because the mean of its divisors is an integer number (3332430870).

Almost surely, 2^51565565616 is an apocalyptic number.

It is an amenable number.

51565565616 is an abundant number, since it is smaller than the sum of its proper divisors (81731669184).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51565565616 is a wasteful number, since it uses less digits than its factorization.

51565565616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695093 (or 695087 counting only the distinct ones).

The product of its digits is 4050000, while the sum is 51.

The spelling of 51565565616 in words is "fifty-one billion, five hundred sixty-five million, five hundred sixty-five thousand, six hundred sixteen".