51610561616 has 20 divisors (see below), whose sum is σ = 100002305172. Its totient is φ = 25803515136.

The previous prime is 51610561601. The next prime is 51610561633. The reversal of 51610561616 is 61616501615.

It can be written as a sum of positive squares in 2 ways, for example, as 29242368016 + 22368193600 = 171004^2 + 149560^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51610561616.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 149306 + ... + 354278.

Almost surely, 2^51610561616 is an apocalyptic number.

It is an amenable number.

51610561616 is a deficient number, since it is larger than the sum of its proper divisors (48391743556).

51610561616 is a wasteful number, since it uses less digits than its factorization.

51610561616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220718 (or 220712 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 38.

The spelling of 51610561616 in words is "fifty-one billion, six hundred ten million, five hundred sixty-one thousand, six hundred sixteen".