393991172 has 12 divisors (see below), whose sum is σ = 693337680. Its totient is φ = 195894696.

The previous prime is 393991159. The next prime is 393991189. The reversal of 393991172 is 271199393.

It is a super-2 number, since 2×393991172² = 310458087227867168, which contains 22 as substring.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 274418 + ... + 275849.

It is an arithmetic number, because the mean of its divisors is an integer number (57778140).

Almost surely, 2^393991172 is an apocalyptic number.

It is an amenable number.

393991172 is a deficient number, since it is larger than the sum of its proper divisors (299346508).

393991172 is a wasteful number, since it uses less digits than its factorization.

393991172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550450 (or 550448 counting only the distinct ones).

The product of its digits is 91854, while the sum is 44.

The square root of 393991172 is about 19849.2108659261. The cubic root of 393991172 is about 733.0982176482.

The spelling of 393991172 in words is "three hundred ninety-three million, nine hundred ninety-one thousand, one hundred seventy-two".