21233331231 has 32 divisors (see below), whose sum is σ = 34114429440. Its totient is φ = 11475851904.

The previous prime is 21233331221. The next prime is 21233331257. The reversal of 21233331231 is 13213333212.

It is not a de Polignac number, because 21233331231 - 2⁶ = 21233331167 is a prime.

It is a super-2 number, since 2×21233331231² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21233331221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 201181 + ... + 287993.

It is an arithmetic number, because the mean of its divisors is an integer number (1066075920).

Almost surely, 2^21233331231 is an apocalyptic number.

21233331231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21233331231 is a deficient number, since it is larger than the sum of its proper divisors (12881098209).

21233331231 is a wasteful number, since it uses less digits than its factorization.

21233331231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87455.

The product of its digits is 1944, while the sum is 24.

Adding to 21233331231 its reverse (13213333212), we get a palindrome (34446664443).

The spelling of 21233331231 in words is "twenty-one billion, two hundred thirty-three million, three hundred thirty-one thousand, two hundred thirty-one".