51660511656 has 64 divisors (see below), whose sum is σ = 139409061120. Its totient is φ = 15858620160.

The previous prime is 51660511603. The next prime is 51660511673. The reversal of 51660511656 is 65611506615.

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, 57615 + ... + 326558.

It is an arithmetic number, because the mean of its divisors is an integer number (2178266580).

Almost surely, 2^51660511656 is an apocalyptic number.

It is an amenable number.

51660511656 is an abundant number, since it is smaller than the sum of its proper divisors (87748549464).

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

51660511656 is a wasteful number, since it uses less digits than its factorization.

51660511656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384626 (or 384622 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 42.

The spelling of 51660511656 in words is "fifty-one billion, six hundred sixty million, five hundred eleven thousand, six hundred fifty-six".