21232023121 has 16 divisors (see below), whose sum is σ = 21507349248. Its totient is φ = 20959027200.

The previous prime is 21232023107. The next prime is 21232023149. The reversal of 21232023121 is 12132023212.

It is a cyclic number.

It is not a de Polignac number, because 21232023121 - 2¹⁷ = 21231892049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21232023221) 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, 25797916 + ... + 25798738.

It is an arithmetic number, because the mean of its divisors is an integer number (1344209328).

Almost surely, 2^21232023121 is an apocalyptic number.

It is an amenable number.

21232023121 is a deficient number, since it is larger than the sum of its proper divisors (275326127).

21232023121 is a wasteful number, since it uses less digits than its factorization.

21232023121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1872.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21232023121 its reverse (12132023212), we get a palindrome (33364046333).

Subtracting from 21232023121 its reverse (12132023212), we obtain a palindrome (9099999909).

The spelling of 21232023121 in words is "twenty-one billion, two hundred thirty-two million, twenty-three thousand, one hundred twenty-one".