166579075881 has 45 divisors (see below), whose sum is σ = 251889505813. Its totient is φ = 109708300800.

The previous prime is 166579075841. The next prime is 166579075889. The reversal of 166579075881 is 188570975661.

The square root of 166579075881 is 408141.

It is a perfect power (a square), and thus also a powerful number.

166579075881 is a `hidden beast` number, since 1 + 6 + 6 + 579 + 0 + 7 + 58 + 8 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 68822800281 + 97756275600 = 262341^2 + 312660^2 .

It is not a de Polignac number, because 166579075881 - 2³⁷ = 29140122409 is a prime.

It is a super-2 number, since 2×166579075881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166579075889) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 370999945 + ... + 371000393.

Almost surely, 2^166579075881 is an apocalyptic number.

166579075881 is the 408141-st square number.

166579075881 is the 204071-st centered octagonal number.

It is an amenable number.

166579075881 is a deficient number, since it is larger than the sum of its proper divisors (85310429932).

166579075881 is an frugal number, since it uses more digits than its factorization.

166579075881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1112 (or 553 counting only the distinct ones).

The product of its (nonzero) digits is 25401600, while the sum is 63.

The spelling of 166579075881 in words is "one hundred sixty-six billion, five hundred seventy-nine million, seventy-five thousand, eight hundred eighty-one".