21021321123231 has 32 divisors (see below), whose sum is σ = 32936711173632. Its totient is φ = 11757248165760.

The previous prime is 21021321123221. The next prime is 21021321123233. The reversal of 21021321123231 is 13232112312012.

It is not a de Polignac number, because 21021321123231 - 2⁶ = 21021321123167 is a prime.

It is a super-2 number, since 2×21021321123231² (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 (21021321123233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4383675 + ... + 7826828.

It is an arithmetic number, because the mean of its divisors is an integer number (1029272224176).

Almost surely, 2^{21021321123231} is an apocalyptic number.

21021321123231 is a deficient number, since it is larger than the sum of its proper divisors (11915390050401).

21021321123231 is a wasteful number, since it uses less digits than its factorization.

21021321123231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12214543.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21021321123231 its reverse (13232112312012), we get a palindrome (34253433435243).

The spelling of 21021321123231 in words is "twenty-one trillion, twenty-one billion, three hundred twenty-one million, one hundred twenty-three thousand, two hundred thirty-one".