31982 has 4 divisors (see below), whose sum is σ = 47976. Its totient is φ = 15990.

The previous prime is 31981. The next prime is 31991. The reversal of 31982 is 28913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 28913 = 29 ⋅997.

It is a plaindrome in base 16.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7994 + ... + 7997.

It is an arithmetic number, because the mean of its divisors is an integer number (11994).

2³¹⁹⁸² is an apocalyptic number.

31982 is a deficient number, since it is larger than the sum of its proper divisors (15994).

31982 is a wasteful number, since it uses less digits than its factorization.

31982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15993.

The product of its digits is 432, while the sum is 23.

The square root of 31982 is about 178.8351195934. The cubic root of 31982 is about 31.7420671689.

The spelling of 31982 in words is "thirty-one thousand, nine hundred eighty-two".