21317500099 has 16 divisors (see below), whose sum is σ = 25243280640. Its totient is φ = 17623513440.

The previous prime is 21317500049. The next prime is 21317500103. The reversal of 21317500099 is 99000571312.

It is a cyclic number.

It is not a de Polignac number, because 21317500099 - 2⁷ = 21317499971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21317500019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 465057 + ... + 508834.

It is an arithmetic number, because the mean of its divisors is an integer number (1577705040).

Almost surely, 2^21317500099 is an apocalyptic number.

21317500099 is a deficient number, since it is larger than the sum of its proper divisors (3925780541).

21317500099 is an equidigital number, since it uses as much as digits as its factorization.

21317500099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974010.

The product of its (nonzero) digits is 17010, while the sum is 37.

The spelling of 21317500099 in words is "twenty-one billion, three hundred seventeen million, five hundred thousand, ninety-nine".