31013213121 has 32 divisors (see below), whose sum is σ = 50422579200. Its totient is φ = 18683306640.

The previous prime is 31013213057. The next prime is 31013213123. The reversal of 31013213121 is 12131231013.

31013213121 is a `hidden beast` number, since 31 + 0 + 1 + 321 + 312 + 1 = 666.

It is not a de Polignac number, because 31013213121 - 2⁶ = 31013213057 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31013213094 and 31013213103.

It is not an unprimeable number, because it can be changed into a prime (31013213123) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 263041 + ... + 362238.

It is an arithmetic number, because the mean of its divisors is an integer number (1575705600).

Almost surely, 2^31013213121 is an apocalyptic number.

It is an amenable number.

31013213121 is a deficient number, since it is larger than the sum of its proper divisors (19409366079).

31013213121 is a wasteful number, since it uses less digits than its factorization.

31013213121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625466 (or 625460 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 31013213121 its reverse (12131231013), we get a palindrome (43144444134).

The spelling of 31013213121 in words is "thirty-one billion, thirteen million, two hundred thirteen thousand, one hundred twenty-one".