21264212807 has 2 divisors, whose sum is σ = 21264212808. Its totient is φ = 21264212806.

The previous prime is 21264212777. The next prime is 21264212857. The reversal of 21264212807 is 70821246212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21264212807 - 2⁶ = 21264212743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21264212857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10632106403 + 10632106404.

It is an arithmetic number, because the mean of its divisors is an integer number (10632106404).

Almost surely, 2^21264212807 is an apocalyptic number.

21264212807 is a deficient number, since it is larger than the sum of its proper divisors (1).

21264212807 is an equidigital number, since it uses as much as digits as its factorization.

21264212807 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21504, while the sum is 35.

The spelling of 21264212807 in words is "twenty-one billion, two hundred sixty-four million, two hundred twelve thousand, eight hundred seven".