166220872 has 32 divisors (see below), whose sum is σ = 321103800. Its totient is φ = 80607744.

The previous prime is 166220809. The next prime is 166220881. The reversal of 166220872 is 278022661.

It can be written as a sum of positive squares in 4 ways, for example, as 138909796 + 27311076 = 11786^2 + 5226^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120378 + ... + 121750.

Almost surely, 2^166220872 is an apocalyptic number.

It is an amenable number.

166220872 is a deficient number, since it is larger than the sum of its proper divisors (154882928).

166220872 is a wasteful number, since it uses less digits than its factorization.

166220872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1825 (or 1821 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 166220872 is about 12892.6673733561. The cubic root of 166220872 is about 549.8301095111.

The spelling of 166220872 in words is "one hundred sixty-six million, two hundred twenty thousand, eight hundred seventy-two".