166311531556 has 24 divisors (see below), whose sum is σ = 310517909856. Its totient is φ = 77666808960.

The previous prime is 166311531541. The next prime is 166311531559. The reversal of 166311531556 is 655135113661.

It is a super-2 number, since 2×166311531556² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166311531559) 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, 9326046 + ... + 9343861.

It is an arithmetic number, because the mean of its divisors is an integer number (12938246244).

Almost surely, 2^166311531556 is an apocalyptic number.

It is an amenable number.

166311531556 is a deficient number, since it is larger than the sum of its proper divisors (144206378300).

166311531556 is a wasteful number, since it uses less digits than its factorization.

166311531556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18670059 (or 18670057 counting only the distinct ones).

The product of its digits is 243000, while the sum is 43.

The spelling of 166311531556 in words is "one hundred sixty-six billion, three hundred eleven million, five hundred thirty-one thousand, five hundred fifty-six".