21257422075913 has 4 divisors (see below), whose sum is σ = 22181657818368. Its totient is φ = 20333186333460.

The previous prime is 21257422075909. The next prime is 21257422075931. The reversal of 21257422075913 is 31957022475212.

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 21257422075913 - 2² = 21257422075909 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21257422075213) 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, 462117871193 + ... + 462117871238.

It is an arithmetic number, because the mean of its divisors is an integer number (5545414454592).

Almost surely, 2^{21257422075913} is an apocalyptic number.

21257422075913 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21257422075913 is a deficient number, since it is larger than the sum of its proper divisors (924235742455).

21257422075913 is an equidigital number, since it uses as much as digits as its factorization.

21257422075913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 924235742454.

The product of its (nonzero) digits is 2116800, while the sum is 50.

The spelling of 21257422075913 in words is "twenty-one trillion, two hundred fifty-seven billion, four hundred twenty-two million, seventy-five thousand, nine hundred thirteen".