31977 has 24 divisors (see below), whose sum is σ = 56160. Its totient is φ = 17280.

The previous prime is 31973. The next prime is 31981. The reversal of 31977 is 77913.

It is an interprime number because it is at equal distance from previous prime (31973) and next prime (31981).

It is not a de Polignac number, because 31977 - 2² = 31973 is a prime.

31977 is a lucky number.

It is a nialpdrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 31977.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 31977.

It is not an unprimeable number, because it can be changed into a prime (31973) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1674 + ... + 1692.

It is an arithmetic number, because the mean of its divisors is an integer number (2340).

2³¹⁹⁷⁷ is an apocalyptic number.

It is an amenable number.

31977 is a deficient number, since it is larger than the sum of its proper divisors (24183).

31977 is a wasteful number, since it uses less digits than its factorization.

31977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53 (or 50 counting only the distinct ones).

The product of its digits is 1323, while the sum is 27.

The square root of 31977 is about 178.8211396899. The cubic root of 31977 is about 31.7404129196.

The spelling of 31977 in words is "thirty-one thousand, nine hundred seventy-seven".