31030013021 has 16 divisors (see below), whose sum is σ = 37466288640. Its totient is φ = 25133619840.

The previous prime is 31030013017. The next prime is 31030013059. The reversal of 31030013021 is 12031003013.

It is not a de Polignac number, because 31030013021 - 2² = 31030013017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31030012987 and 31030013005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31030013821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1616600 + ... + 1635681.

It is an arithmetic number, because the mean of its divisors is an integer number (2341643040).

Almost surely, 2^31030013021 is an apocalyptic number.

It is an amenable number.

31030013021 is a deficient number, since it is larger than the sum of its proper divisors (6436275619).

31030013021 is a wasteful number, since it uses less digits than its factorization.

31030013021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3252364.

The product of its (nonzero) digits is 54, while the sum is 14.

Adding to 31030013021 its reverse (12031003013), we get a palindrome (43061016034).

The spelling of 31030013021 in words is "thirty-one billion, thirty million, thirteen thousand, twenty-one".