161511660656 has 40 divisors (see below), whose sum is σ = 313976622960. Its totient is φ = 80485622784.

The previous prime is 161511660649. The next prime is 161511660683. The reversal of 161511660656 is 656066115161.

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, 22313870 + ... + 22321106.

It is an arithmetic number, because the mean of its divisors is an integer number (7849415574).

Almost surely, 2^161511660656 is an apocalyptic number.

161511660656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

161511660656 is a deficient number, since it is larger than the sum of its proper divisors (152464962304).

161511660656 is a wasteful number, since it uses less digits than its factorization.

161511660656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11721 (or 11715 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 44.

The spelling of 161511660656 in words is "one hundred sixty-one billion, five hundred eleven million, six hundred sixty thousand, six hundred fifty-six".