31974157 has 2 divisors, whose sum is σ = 31974158. Its totient is φ = 31974156.

The previous prime is 31974143. The next prime is 31974167. The reversal of 31974157 is 75147913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25593481 + 6380676 = 5059^2 + 2526^2 .

It is a cyclic number.

It is not a de Polignac number, because 31974157 - 2⁷ = 31974029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31974167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15987078 + 15987079.

It is an arithmetic number, because the mean of its divisors is an integer number (15987079).

Almost surely, 2^31974157 is an apocalyptic number.

It is an amenable number.

31974157 is a deficient number, since it is larger than the sum of its proper divisors (1).

31974157 is an equidigital number, since it uses as much as digits as its factorization.

31974157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26460, while the sum is 37.

The square root of 31974157 is about 5654.5695680573. The cubic root of 31974157 is about 317.3947223651.

It can be divided in two parts, 31974 and 157, that added together give a triangular number (32131 = T₂₅₃).

The spelling of 31974157 in words is "thirty-one million, nine hundred seventy-four thousand, one hundred fifty-seven".