21668211807573 has 8 divisors (see below), whose sum is σ = 29380626180000. Its totient is φ = 14200635986768.

The previous prime is 21668211807563. The next prime is 21668211807637. The reversal of 21668211807573 is 37570811286612.

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

It is a cyclic number.

It is not a de Polignac number, because 21668211807573 - 2⁸ = 21668211807317 is a prime.

It is a super-2 number, since 2×21668211807573² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21668211807563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61209637698 + ... + 61209638051.

It is an arithmetic number, because the mean of its divisors is an integer number (3672578272500).

Almost surely, 2^{21668211807573} is an apocalyptic number.

It is an amenable number.

21668211807573 is a deficient number, since it is larger than the sum of its proper divisors (7712414372427).

21668211807573 is a wasteful number, since it uses less digits than its factorization.

21668211807573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122419275811.

The product of its (nonzero) digits is 6773760, while the sum is 57.

The spelling of 21668211807573 in words is "twenty-one trillion, six hundred sixty-eight billion, two hundred eleven million, eight hundred seven thousand, five hundred seventy-three".