51501565655 has 8 divisors (see below), whose sum is σ = 62125449984. Its totient is φ = 40985538400.

The previous prime is 51501565651. The next prime is 51501565657. The reversal of 51501565655 is 55656510515.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51501565655 - 2² = 51501565651 is a prime.

It is a super-2 number, since 2×51501565655² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51501565651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26963216 + ... + 26965125.

It is an arithmetic number, because the mean of its divisors is an integer number (7765681248).

Almost surely, 2^51501565655 is an apocalyptic number.

51501565655 is a deficient number, since it is larger than the sum of its proper divisors (10623884329).

51501565655 is a wasteful number, since it uses less digits than its factorization.

51501565655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53928537.

The product of its (nonzero) digits is 562500, while the sum is 44.

The spelling of 51501565655 in words is "fifty-one billion, five hundred one million, five hundred sixty-five thousand, six hundred fifty-five".