21663265339 has 2 divisors, whose sum is σ = 21663265340. Its totient is φ = 21663265338.

The previous prime is 21663265259. The next prime is 21663265399. The reversal of 21663265339 is 93356236612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21663265339 - 2²⁹ = 21126394427 is a prime.

It is not a weakly prime, because it can be changed into another prime (21663265399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10831632669 + 10831632670.

It is an arithmetic number, because the mean of its divisors is an integer number (10831632670).

Almost surely, 2^21663265339 is an apocalyptic number.

21663265339 is a deficient number, since it is larger than the sum of its proper divisors (1).

21663265339 is an equidigital number, since it uses as much as digits as its factorization.

21663265339 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1049760, while the sum is 46.

The spelling of 21663265339 in words is "twenty-one billion, six hundred sixty-three million, two hundred sixty-five thousand, three hundred thirty-nine".