172331631 has 20 divisors (see below), whose sum is σ = 258299184. Its totient is φ = 114501600.

The previous prime is 172331623. The next prime is 172331633. The reversal of 172331631 is 136133271.

172331631 is a `hidden beast` number, since 1 + 7 + 23 + 3 + 1 + 631 = 666.

172331631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 172331631 - 2³ = 172331623 is a prime.

It is a super-2 number, since 2×172331631² = 59396382086240322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 172331595 and 172331604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172331633) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 21771 + ... + 28611.

Almost surely, 2^172331631 is an apocalyptic number.

172331631 is a deficient number, since it is larger than the sum of its proper divisors (85967553).

172331631 is an equidigital number, since it uses as much as digits as its factorization.

172331631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7164 (or 7155 counting only the distinct ones).

The product of its digits is 2268, while the sum is 27.

The square root of 172331631 is about 13127.5142734640. The cubic root of 172331631 is about 556.4869694205.

The spelling of 172331631 in words is "one hundred seventy-two million, three hundred thirty-one thousand, six hundred thirty-one".