21365555235659 has 2 divisors, whose sum is σ = 21365555235660. Its totient is φ = 21365555235658.

The previous prime is 21365555235601. The next prime is 21365555235677. The reversal of 21365555235659 is 95653255556312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21365555235659 - 2²⁰ = 21365554187083 is a prime.

It is not a weakly prime, because it can be changed into another prime (21365555235559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10682777617829 + 10682777617830.

It is an arithmetic number, because the mean of its divisors is an integer number (10682777617830).

Almost surely, 2^{21365555235659} is an apocalyptic number.

21365555235659 is a deficient number, since it is larger than the sum of its proper divisors (1).

21365555235659 is an equidigital number, since it uses as much as digits as its factorization.

21365555235659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 182250000, while the sum is 62.

The spelling of 21365555235659 in words is "twenty-one trillion, three hundred sixty-five billion, five hundred fifty-five million, two hundred thirty-five thousand, six hundred fifty-nine".