21321211131231 has 16 divisors (see below), whose sum is σ = 32082073176960. Its totient is φ = 12476361789920.

The previous prime is 21321211131163. The next prime is 21321211131293. The reversal of 21321211131231 is 13213111212312.

It is a cyclic number.

It is not a de Polignac number, because 21321211131231 - 2⁹ = 21321211130719 is a prime.

It is a super-2 number, since 2×21321211131231² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321211133231) 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, 11139607785 + ... + 11139609698.

It is an arithmetic number, because the mean of its divisors is an integer number (2005129573560).

Almost surely, 2^{21321211131231} is an apocalyptic number.

21321211131231 is a deficient number, since it is larger than the sum of its proper divisors (10760862045729).

21321211131231 is a wasteful number, since it uses less digits than its factorization.

21321211131231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22279217526.

The product of its digits is 432, while the sum is 24.

Adding to 21321211131231 its reverse (13213111212312), we get a palindrome (34534322343543).

The spelling of 21321211131231 in words is "twenty-one trillion, three hundred twenty-one billion, two hundred eleven million, one hundred thirty-one thousand, two hundred thirty-one".