31990839 has 8 divisors (see below), whose sum is σ = 43646592. Its totient is φ = 20831160.

The previous prime is 31990831. The next prime is 31990897. The reversal of 31990839 is 93809913.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31990839 - 2³ = 31990831 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 31990839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31990831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123867 + ... + 124124.

It is an arithmetic number, because the mean of its divisors is an integer number (5455824).

Almost surely, 2^31990839 is an apocalyptic number.

31990839 is a deficient number, since it is larger than the sum of its proper divisors (11655753).

31990839 is a wasteful number, since it uses less digits than its factorization.

31990839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248037.

The product of its (nonzero) digits is 52488, while the sum is 42.

The square root of 31990839 is about 5656.0444658790. The cubic root of 31990839 is about 317.4499112916.

The spelling of 31990839 in words is "thirty-one million, nine hundred ninety thousand, eight hundred thirty-nine".