21312312123013 has 4 divisors (see below), whose sum is σ = 21314489747200. Its totient is φ = 21310134498828.

The previous prime is 21312312122999. The next prime is 21312312123041. The reversal of 21312312123013 is 31032121321312.

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 21312312123013 - 2⁴¹ = 19113288867461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312312123073) 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, 1088797413 + ... + 1088816986.

It is an arithmetic number, because the mean of its divisors is an integer number (5328622436800).

Almost surely, 2^{21312312123013} is an apocalyptic number.

It is an amenable number.

21312312123013 is a deficient number, since it is larger than the sum of its proper divisors (2177624187).

21312312123013 is an equidigital number, since it uses as much as digits as its factorization.

21312312123013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2177624186.

The product of its (nonzero) digits is 1296, while the sum is 25.

Adding to 21312312123013 its reverse (31032121321312), we get a palindrome (52344433444325).

The spelling of 21312312123013 in words is "twenty-one trillion, three hundred twelve billion, three hundred twelve million, one hundred twenty-three thousand, thirteen".