31967979 has 4 divisors (see below), whose sum is σ = 42623976. Its totient is φ = 21311984.

The previous prime is 31967951. The next prime is 31967983. The reversal of 31967979 is 97976913.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31967979 - 2¹⁶ = 31902443 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31967909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5327994 + ... + 5327999.

It is an arithmetic number, because the mean of its divisors is an integer number (10655994).

Almost surely, 2^31967979 is an apocalyptic number.

31967979 is a deficient number, since it is larger than the sum of its proper divisors (10655997).

31967979 is a wasteful number, since it uses less digits than its factorization.

31967979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10655996.

The product of its digits is 642978, while the sum is 51.

The square root of 31967979 is about 5654.0232578227. The cubic root of 31967979 is about 317.3742788665.

It can be divided in two parts, 3196 and 7979, that added together give a triangular number (11175 = T₁₄₉).

The spelling of 31967979 in words is "thirty-one million, nine hundred sixty-seven thousand, nine hundred seventy-nine".