21417967356799 has 4 divisors (see below), whose sum is σ = 23065503307336. Its totient is φ = 19770431406264.

The previous prime is 21417967356763. The next prime is 21417967356823. The reversal of 21417967356799 is 99765376971412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21417967356799 - 2⁷ = 21417967356671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21417967356199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 823767975249 + ... + 823767975274.

It is an arithmetic number, because the mean of its divisors is an integer number (5766375826834).

Almost surely, 2^{21417967356799} is an apocalyptic number.

21417967356799 is a deficient number, since it is larger than the sum of its proper divisors (1647535950537).

21417967356799 is a wasteful number, since it uses less digits than its factorization.

21417967356799 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1647535950536.

The product of its digits is 1080203040, while the sum is 76.

The spelling of 21417967356799 in words is "twenty-one trillion, four hundred seventeen billion, nine hundred sixty-seven million, three hundred fifty-six thousand, seven hundred ninety-nine".