331991172 has 36 divisors (see below), whose sum is σ = 851026176. Its totient is φ = 109104240.

The previous prime is 331991137. The next prime is 331991173. The reversal of 331991172 is 271199133.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×331991172² = 220436276571867168, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (331991173) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62388 + ... + 67499.

It is an arithmetic number, because the mean of its divisors is an integer number (23639616).

Almost surely, 2^331991172 is an apocalyptic number.

It is an amenable number.

331991172 is an abundant number, since it is smaller than the sum of its proper divisors (519035004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

331991172 is a wasteful number, since it uses less digits than its factorization.

331991172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129968 (or 129963 counting only the distinct ones).

The product of its digits is 10206, while the sum is 36.

The square root of 331991172 is about 18220.6249069564. The cubic root of 331991172 is about 692.4294198377.

The spelling of 331991172 in words is "three hundred thirty-one million, nine hundred ninety-one thousand, one hundred seventy-two".