31318039 has 4 divisors (see below), whose sum is σ = 31557240. Its totient is φ = 31078840.

The previous prime is 31318037. The next prime is 31318043. The reversal of 31318039 is 93081313.

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 31318039 - 2¹ = 31318037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31317998 and 31318016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31318031) 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, 119404 + ... + 119665.

It is an arithmetic number, because the mean of its divisors is an integer number (7889310).

Almost surely, 2^31318039 is an apocalyptic number.

31318039 is a deficient number, since it is larger than the sum of its proper divisors (239201).

31318039 is a wasteful number, since it uses less digits than its factorization.

31318039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239200.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 31318039 is about 5596.2522280541. The cubic root of 31318039 is about 315.2086934857.

The spelling of 31318039 in words is "thirty-one million, three hundred eighteen thousand, thirty-nine".