51661165560 has 32 divisors (see below), whose sum is σ = 154983497040. Its totient is φ = 13776310784.

The previous prime is 51661165519. The next prime is 51661165571. The reversal of 51661165560 is 6556116615.

It is a super-2 number, since 2×51661165560² (a number of 22 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

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, 215254737 + ... + 215254976.

Almost surely, 2^51661165560 is an apocalyptic number.

It is an amenable number.

51661165560 is an abundant number, since it is smaller than the sum of its proper divisors (103322331480).

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

51661165560 is a wasteful number, since it uses less digits than its factorization.

51661165560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430509727 (or 430509723 counting only the distinct ones).

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

The spelling of 51661165560 in words is "fifty-one billion, six hundred sixty-one million, one hundred sixty-five thousand, five hundred sixty".