21012210131 has 16 divisors (see below), whose sum is σ = 23169269760. Its totient is φ = 18896474880.

The previous prime is 21012210113. The next prime is 21012210139. The reversal of 21012210131 is 13101221012.

It is a cyclic number.

It is not a de Polignac number, because 21012210131 - 2³⁴ = 3832340947 is a prime.

It is a super-2 number, since 2×21012210131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012210139) 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, 4102190 + ... + 4107308.

It is an arithmetic number, because the mean of its divisors is an integer number (1448079360).

Almost surely, 2^21012210131 is an apocalyptic number.

21012210131 is a deficient number, since it is larger than the sum of its proper divisors (2157059629).

21012210131 is a wasteful number, since it uses less digits than its factorization.

21012210131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9074.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21012210131 its reverse (13101221012), we get a palindrome (34113431143).

The spelling of 21012210131 in words is "twenty-one billion, twelve million, two hundred ten thousand, one hundred thirty-one".