31133172 has 48 divisors (see below), whose sum is σ = 87395840. Its totient is φ = 8426592.

The previous prime is 31133147. The next prime is 31133183. The reversal of 31133172 is 27133113.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8158 + ... + 11349.

Almost surely, 2^31133172 is an apocalyptic number.

It is an amenable number.

31133172 is an abundant number, since it is smaller than the sum of its proper divisors (56262668).

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

31133172 is a wasteful number, since it uses less digits than its factorization.

31133172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19540 (or 19538 counting only the distinct ones).

The product of its digits is 378, while the sum is 21.

The square root of 31133172 is about 5579.7107451910. The cubic root of 31133172 is about 314.5872548298.

Adding to 31133172 its reverse (27133113), we get a palindrome (58266285).

The spelling of 31133172 in words is "thirty-one million, one hundred thirty-three thousand, one hundred seventy-two".