21022131213 has 12 divisors (see below), whose sum is σ = 30665948508. Its totient is φ = 13875993600.

The previous prime is 21022131211. The next prime is 21022131289. The reversal of 21022131213 is 31213122012.

It can be written as a sum of positive squares in 2 ways, for example, as 14632047369 + 6390083844 = 120963^2 + 79938^2 .

It is not a de Polignac number, because 21022131213 - 2¹ = 21022131211 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022131211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11562420 + ... + 11564237.

It is an arithmetic number, because the mean of its divisors is an integer number (2555495709).

Almost surely, 2^21022131213 is an apocalyptic number.

It is an amenable number.

21022131213 is a deficient number, since it is larger than the sum of its proper divisors (9643817295).

21022131213 is a wasteful number, since it uses less digits than its factorization.

21022131213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23126764 (or 23126761 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21022131213 its reverse (31213122012), we get a palindrome (52235253225).

The spelling of 21022131213 in words is "twenty-one billion, twenty-two million, one hundred thirty-one thousand, two hundred thirteen".