31868639 has 8 divisors (see below), whose sum is σ = 36277632. Its totient is φ = 27711640.

The previous prime is 31868561. The next prime is 31868647. The reversal of 31868639 is 93686813.

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

It is not a de Polignac number, because 31868639 - 2⁸ = 31868383 is a prime.

It is a super-2 number, since 2×31868639² = 2031220303424642, which contains 22 as substring.

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 31868639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31868689) 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, 62729 + ... + 63234.

It is an arithmetic number, because the mean of its divisors is an integer number (4534704).

Almost surely, 2^31868639 is an apocalyptic number.

31868639 is a deficient number, since it is larger than the sum of its proper divisors (4408993).

31868639 is a wasteful number, since it uses less digits than its factorization.

31868639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125997.

The product of its digits is 186624, while the sum is 44.

The square root of 31868639 is about 5645.2315275815. The cubic root of 31868639 is about 317.0451925339.

The spelling of 31868639 in words is "thirty-one million, eight hundred sixty-eight thousand, six hundred thirty-nine".