31971986 has 16 divisors (see below), whose sum is σ = 48539520. Its totient is φ = 15793680.

The previous prime is 31971977. The next prime is 31972009. The reversal of 31971986 is 68917913.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100700 + ... + 101016.

It is an arithmetic number, because the mean of its divisors is an integer number (3033720).

Almost surely, 2^31971986 is an apocalyptic number.

31971986 is a deficient number, since it is larger than the sum of its proper divisors (16567534).

31971986 is a wasteful number, since it uses less digits than its factorization.

31971986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 769.

The product of its digits is 81648, while the sum is 44.

The square root of 31971986 is about 5654.3775961639. The cubic root of 31971986 is about 317.3875386517.

The spelling of 31971986 in words is "thirty-one million, nine hundred seventy-one thousand, nine hundred eighty-six".