21637633013 has 2 divisors, whose sum is σ = 21637633014. Its totient is φ = 21637633012.

The previous prime is 21637632899. The next prime is 21637633081. The reversal of 21637633013 is 31033673612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16635324484 + 5002308529 = 128978^2 + 70727^2 .

It is a cyclic number.

It is not a de Polignac number, because 21637633013 - 2¹⁸ = 21637370869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21637632013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10818816506 + 10818816507.

It is an arithmetic number, because the mean of its divisors is an integer number (10818816507).

Almost surely, 2^21637633013 is an apocalyptic number.

It is an amenable number.

21637633013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21637633013 is an equidigital number, since it uses as much as digits as its factorization.

21637633013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 35.

The spelling of 21637633013 in words is "twenty-one billion, six hundred thirty-seven million, six hundred thirty-three thousand, thirteen".