31012013231 has 4 divisors (see below), whose sum is σ = 31015245552. Its totient is φ = 31008780912.

The previous prime is 31012013209. The next prime is 31012013261. The reversal of 31012013231 is 13231021013.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31012013231 is a prime.

It is a super-2 number, since 2×31012013231² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31012013261) 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, 1601726 + ... + 1620971.

It is an arithmetic number, because the mean of its divisors is an integer number (7753811388).

Almost surely, 2^31012013231 is an apocalyptic number.

31012013231 is a deficient number, since it is larger than the sum of its proper divisors (3232321).

31012013231 is an equidigital number, since it uses as much as digits as its factorization.

31012013231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3232320.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 31012013231 its reverse (13231021013), we get a palindrome (44243034244).

The spelling of 31012013231 in words is "thirty-one billion, twelve million, thirteen thousand, two hundred thirty-one".