31989479 has 4 divisors (see below), whose sum is σ = 32111376. Its totient is φ = 31867584.

The previous prime is 31989443. The next prime is 31989487. The reversal of 31989479 is 97498913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97498913 = 4651 ⋅20963.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31989479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31989439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60554 + ... + 61079.

It is an arithmetic number, because the mean of its divisors is an integer number (8027844).

Almost surely, 2^31989479 is an apocalyptic number.

31989479 is a deficient number, since it is larger than the sum of its proper divisors (121897).

31989479 is a wasteful number, since it uses less digits than its factorization.

31989479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121896.

The product of its digits is 489888, while the sum is 50.

The square root of 31989479 is about 5655.9242392380. The cubic root of 31989479 is about 317.4454127329.

It can be divided in two parts, 319 and 89479, that added together give a palindrome (89798).

The spelling of 31989479 in words is "thirty-one million, nine hundred eighty-nine thousand, four hundred seventy-nine".