21211013021 has 32 divisors (see below), whose sum is σ = 24060032640. Its totient is φ = 18531251200.

The previous prime is 21211013017. The next prime is 21211013041. The reversal of 21211013021 is 12031011212.

It is not a de Polignac number, because 21211013021 - 2² = 21211013017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21211012987 and 21211013005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211013041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12723230 + ... + 12724896.

It is an arithmetic number, because the mean of its divisors is an integer number (751876020).

Almost surely, 2^21211013021 is an apocalyptic number.

It is an amenable number.

21211013021 is a deficient number, since it is larger than the sum of its proper divisors (2849019619).

21211013021 is a wasteful number, since it uses less digits than its factorization.

21211013021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2125.

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

Adding to 21211013021 its reverse (12031011212), we get a palindrome (33242024233).

The spelling of 21211013021 in words is "twenty-one billion, two hundred eleven million, thirteen thousand, twenty-one".