164518660881 has 27 divisors (see below), whose sum is σ = 242301384507. Its totient is φ = 107567506800.

The previous prime is 164518660849. The next prime is 164518660883. The reversal of 164518660881 is 188066815461.

The square root of 164518660881 is 405609.

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

164518660881 is a `hidden beast` number, since 1 + 64 + 518 + 6 + 60 + 8 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 118601028225 + 45917632656 = 344385^2 + 214284^2 .

It is not a de Polignac number, because 164518660881 - 2⁵ = 164518660849 is a prime.

It is a super-2 number, since 2×164518660881² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (164518660883) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 64490556 + ... + 64493106.

Almost surely, 2^164518660881 is an apocalyptic number.

164518660881 is the 405609-th square number.

164518660881 is the 202805-th centered octagonal number.

It is an amenable number.

164518660881 is a deficient number, since it is larger than the sum of its proper divisors (77782723626).

164518660881 is an frugal number, since it uses more digits than its factorization.

164518660881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5214 (or 2607 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 54.

The spelling of 164518660881 in words is "one hundred sixty-four billion, five hundred eighteen million, six hundred sixty thousand, eight hundred eighty-one".