21131202233 has 4 divisors (see below), whose sum is σ = 21174593280. Its totient is φ = 21087811188.

The previous prime is 21131202227. The next prime is 21131202247. The reversal of 21131202233 is 33220213112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21131202233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21131202133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21694793 + ... + 21695766.

It is an arithmetic number, because the mean of its divisors is an integer number (5293648320).

Almost surely, 2^21131202233 is an apocalyptic number.

It is an amenable number.

21131202233 is a deficient number, since it is larger than the sum of its proper divisors (43391047).

21131202233 is an equidigital number, since it uses as much as digits as its factorization.

21131202233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43391046.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21131202233 its reverse (33220213112), we get a palindrome (54351415345).

The spelling of 21131202233 in words is "twenty-one billion, one hundred thirty-one million, two hundred two thousand, two hundred thirty-three".