31972231 has 12 divisors (see below), whose sum is σ = 35192920. Its totient is φ = 28963440.

The previous prime is 31972229. The next prime is 31972273. The reversal of 31972231 is 13227913.

It is not a de Polignac number, because 31972231 - 2¹ = 31972229 is a prime.

It is a super-2 number, since 2×31972231² = 2044447110234722, which contains 22 as substring.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31972231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31972331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8461 + ... + 11641.

Almost surely, 2^31972231 is an apocalyptic number.

31972231 is a deficient number, since it is larger than the sum of its proper divisors (3220689).

31972231 is a wasteful number, since it uses less digits than its factorization.

31972231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3246 (or 3223 counting only the distinct ones).

The product of its digits is 2268, while the sum is 28.

The square root of 31972231 is about 5654.3992607526. The cubic root of 31972231 is about 317.3883493588.

The spelling of 31972231 in words is "thirty-one million, nine hundred seventy-two thousand, two hundred thirty-one".