51566066555 has 4 divisors (see below), whose sum is σ = 61879279872. Its totient is φ = 41252853240.

The previous prime is 51566066549. The next prime is 51566066567. The reversal of 51566066555 is 55566066515.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 51566066555 - 2²² = 51561872251 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5156606651 + ... + 5156606660.

It is an arithmetic number, because the mean of its divisors is an integer number (15469819968).

Almost surely, 2^51566066555 is an apocalyptic number.

51566066555 is a deficient number, since it is larger than the sum of its proper divisors (10313213317).

51566066555 is a wasteful number, since it uses less digits than its factorization.

51566066555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10313213316.

The product of its (nonzero) digits is 4050000, while the sum is 50.

The spelling of 51566066555 in words is "fifty-one billion, five hundred sixty-six million, sixty-six thousand, five hundred fifty-five".