31312643 has 8 divisors (see below), whose sum is σ = 32824176. Its totient is φ = 29836800.

The previous prime is 31312613. The next prime is 31312679. The reversal of 31312643 is 34621313.

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

It is a cyclic number.

It is not a de Polignac number, because 31312643 - 2⁶ = 31312579 is a prime.

It is a super-2 number, since 2×31312643² = 1960963223290898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31312613) 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, 7118 + ... + 10643.

It is an arithmetic number, because the mean of its divisors is an integer number (4103022).

Almost surely, 2^31312643 is an apocalyptic number.

31312643 is a deficient number, since it is larger than the sum of its proper divisors (1511533).

31312643 is a wasteful number, since it uses less digits than its factorization.

31312643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17845.

The product of its digits is 1296, while the sum is 23.

The square root of 31312643 is about 5595.7700989229. The cubic root of 31312643 is about 315.1905892891.

Adding to 31312643 its reverse (34621313), we get a palindrome (65933956).

The spelling of 31312643 in words is "thirty-one million, three hundred twelve thousand, six hundred forty-three".