21331313123 has 8 divisors (see below), whose sum is σ = 21411912192. Its totient is φ = 21250836936.

The previous prime is 21331313093. The next prime is 21331313147. The reversal of 21331313123 is 32131313312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21331313123 - 2¹⁴ = 21331296739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21331313153) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 324836 + ... + 384942.

It is an arithmetic number, because the mean of its divisors is an integer number (2676489024).

Almost surely, 2^21331313123 is an apocalyptic number.

21331313123 is a deficient number, since it is larger than the sum of its proper divisors (80599069).

21331313123 is an equidigital number, since it uses as much as digits as its factorization.

21331313123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61441.

The product of its digits is 972, while the sum is 23.

Adding to 21331313123 its reverse (32131313312), we get a palindrome (53462626435).

The spelling of 21331313123 in words is "twenty-one billion, three hundred thirty-one million, three hundred thirteen thousand, one hundred twenty-three".