21331312279 has 2 divisors, whose sum is σ = 21331312280. Its totient is φ = 21331312278.

The previous prime is 21331312253. The next prime is 21331312339. The reversal of 21331312279 is 97221313312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21331312279 - 2¹³ = 21331304087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21331312879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10665656139 + 10665656140.

It is an arithmetic number, because the mean of its divisors is an integer number (10665656140).

Almost surely, 2^21331312279 is an apocalyptic number.

21331312279 is a deficient number, since it is larger than the sum of its proper divisors (1).

21331312279 is an equidigital number, since it uses as much as digits as its factorization.

21331312279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 34.

The spelling of 21331312279 in words is "twenty-one billion, three hundred thirty-one million, three hundred twelve thousand, two hundred seventy-nine".