31331929 has 2 divisors, whose sum is σ = 31331930. Its totient is φ = 31331928.

The previous prime is 31331921. The next prime is 31331959. The reversal of 31331929 is 92913313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29680704 + 1651225 = 5448^2 + 1285^2 .

It is a cyclic number.

It is not a de Polignac number, because 31331929 - 2³ = 31331921 is a prime.

It is a super-2 number, since 2×31331929² = 1963379549722082, which contains 22 as substring.

It is equal to p_1935166 and since 31331929 and 1935166 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31331929.

It is not a weakly prime, because it can be changed into another prime (31331921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15665964 + 15665965.

It is an arithmetic number, because the mean of its divisors is an integer number (15665965).

Almost surely, 2^31331929 is an apocalyptic number.

It is an amenable number.

31331929 is a deficient number, since it is larger than the sum of its proper divisors (1).

31331929 is an equidigital number, since it uses as much as digits as its factorization.

31331929 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4374, while the sum is 31.

The square root of 31331929 is about 5597.4930995938. The cubic root of 31331929 is about 315.2552864587.

The spelling of 31331929 in words is "thirty-one million, three hundred thirty-one thousand, nine hundred twenty-nine".