21919113563 has 2 divisors, whose sum is σ = 21919113564. Its totient is φ = 21919113562.

The previous prime is 21919113553. The next prime is 21919113631. The reversal of 21919113563 is 36531191912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21919113563 - 2¹⁸ = 21918851419 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21919113563.

It is not a weakly prime, because it can be changed into another prime (21919113553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10959556781 + 10959556782.

It is an arithmetic number, because the mean of its divisors is an integer number (10959556782).

Almost surely, 2^21919113563 is an apocalyptic number.

21919113563 is a deficient number, since it is larger than the sum of its proper divisors (1).

21919113563 is an equidigital number, since it uses as much as digits as its factorization.

21919113563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740, while the sum is 41.

The spelling of 21919113563 in words is "twenty-one billion, nine hundred nineteen million, one hundred thirteen thousand, five hundred sixty-three".