21317984499 has 8 divisors (see below), whose sum is σ = 32484547840. Its totient is φ = 12181705416.

The previous prime is 21317984473. The next prime is 21317984509. The reversal of 21317984499 is 99448971312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21317984499 - 2⁸ = 21317984243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21317984449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 507571039 + ... + 507571080.

It is an arithmetic number, because the mean of its divisors is an integer number (4060568480).

Almost surely, 2^21317984499 is an apocalyptic number.

21317984499 is a deficient number, since it is larger than the sum of its proper divisors (11166563341).

21317984499 is a wasteful number, since it uses less digits than its factorization.

21317984499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1015142129.

The product of its digits is 3919104, while the sum is 57.

The spelling of 21317984499 in words is "twenty-one billion, three hundred seventeen million, nine hundred eighty-four thousand, four hundred ninety-nine".