21630013123591 has 2 divisors, whose sum is σ = 21630013123592. Its totient is φ = 21630013123590.

The previous prime is 21630013123571. The next prime is 21630013123613. The reversal of 21630013123591 is 19532131003612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21630013123591 - 2¹¹ = 21630013121543 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21630013123591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21630013123561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815006561795 + 10815006561796.

It is an arithmetic number, because the mean of its divisors is an integer number (10815006561796).

Almost surely, 2^{21630013123591} is an apocalyptic number.

21630013123591 is a deficient number, since it is larger than the sum of its proper divisors (1).

21630013123591 is an equidigital number, since it uses as much as digits as its factorization.

21630013123591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 29160, while the sum is 37.

The spelling of 21630013123591 in words is "twenty-one trillion, six hundred thirty billion, thirteen million, one hundred twenty-three thousand, five hundred ninety-one".