31939493 has 4 divisors (see below), whose sum is σ = 32004000. Its totient is φ = 31874988.

The previous prime is 31939483. The next prime is 31939511. The reversal of 31939493 is 39493913.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39493913 = 19 ⋅2078627.

It is a cyclic number.

It is not a de Polignac number, because 31939493 - 2⁴ = 31939477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31939493.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31939403) 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, 31505 + ... + 32502.

It is an arithmetic number, because the mean of its divisors is an integer number (8001000).

Almost surely, 2^31939493 is an apocalyptic number.

It is an amenable number.

31939493 is a deficient number, since it is larger than the sum of its proper divisors (64507).

31939493 is an equidigital number, since it uses as much as digits as its factorization.

31939493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64506.

The product of its digits is 78732, while the sum is 41.

The square root of 31939493 is about 5651.5036052364. The cubic root of 31939493 is about 317.2799823167.

The spelling of 31939493 in words is "thirty-one million, nine hundred thirty-nine thousand, four hundred ninety-three".