31999797 has 24 divisors (see below), whose sum is σ = 49233600. Its totient is φ = 19958400.

The previous prime is 31999787. The next prime is 31999801. The reversal of 31999797 is 79799913.

It is not a de Polignac number, because 31999797 - 2⁶ = 31999733 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31999727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29922 + ... + 30972.

It is an arithmetic number, because the mean of its divisors is an integer number (2051400).

Almost surely, 2^31999797 is an apocalyptic number.

It is an amenable number.

31999797 is a deficient number, since it is larger than the sum of its proper divisors (17233803).

31999797 is a wasteful number, since it uses less digits than its factorization.

31999797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1273 (or 1270 counting only the distinct ones).

The product of its digits is 964467, while the sum is 54.

The square root of 31999797 is about 5656.8363066294. The cubic root of 31999797 is about 317.4795390539.

It can be divided in two parts, 3199 and 9797, that added together give a square (12996 = 114²).

The spelling of 31999797 in words is "thirty-one million, nine hundred ninety-nine thousand, seven hundred ninety-seven".