23121231 has 16 divisors (see below), whose sum is σ = 35760384. Its totient is φ = 13014144.

The previous prime is 23121209. The next prime is 23121247. The reversal of 23121231 is 13212132.

It is not a de Polignac number, because 23121231 - 2⁷ = 23121103 is a prime.

It is a super-2 number, since 2×23121231² = 1069182645910722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 23121231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23121281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6810 + ... + 9623.

It is an arithmetic number, because the mean of its divisors is an integer number (2235024).

Almost surely, 2^23121231 is an apocalyptic number.

23121231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

23121231 is a deficient number, since it is larger than the sum of its proper divisors (12639153).

23121231 is a wasteful number, since it uses less digits than its factorization.

23121231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16510.

The product of its digits is 72, while the sum is 15.

The square root of 23121231 is about 4808.4541174893. The cubic root of 23121231 is about 284.8854818454.

Adding to 23121231 its reverse (13212132), we get a palindrome (36333363).

Subtracting from 23121231 its reverse (13212132), we obtain a palindrome (9909099).

The spelling of 23121231 in words is "twenty-three million, one hundred twenty-one thousand, two hundred thirty-one".