231220133213 has 4 divisors (see below), whose sum is σ = 231317164608. Its totient is φ = 231123101820.

The previous prime is 231220133203. The next prime is 231220133251. The reversal of 231220133213 is 312331022132.

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 not a de Polignac number, because 231220133213 - 2²² = 231215938909 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231220133203) 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, 48512123 + ... + 48516888.

It is an arithmetic number, because the mean of its divisors is an integer number (57829291152).

Almost surely, 2^231220133213 is an apocalyptic number.

It is an amenable number.

231220133213 is a deficient number, since it is larger than the sum of its proper divisors (97031395).

231220133213 is an equidigital number, since it uses as much as digits as its factorization.

231220133213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97031394.

The product of its (nonzero) digits is 1296, while the sum is 23.

Adding to 231220133213 its reverse (312331022132), we get a palindrome (543551155345).

The spelling of 231220133213 in words is "two hundred thirty-one billion, two hundred twenty million, one hundred thirty-three thousand, two hundred thirteen".