21668392360779 has 16 divisors (see below), whose sum is σ = 29674042202112. Its totient is φ = 14054221592928.

The previous prime is 21668392360757. The next prime is 21668392360799. The reversal of 21668392360779 is 97706329386612.

It is not a de Polignac number, because 21668392360779 - 2¹⁹ = 21668391836491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21668392360799) 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, 4961629 + ... + 8243454.

It is an arithmetic number, because the mean of its divisors is an integer number (1854627637632).

Almost surely, 2^{21668392360779} is an apocalyptic number.

21668392360779 is a deficient number, since it is larger than the sum of its proper divisors (8005649841333).

21668392360779 is a wasteful number, since it uses less digits than its factorization.

21668392360779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13219906.

The product of its (nonzero) digits is 246903552, while the sum is 69.

The spelling of 21668392360779 in words is "twenty-one trillion, six hundred sixty-eight billion, three hundred ninety-two million, three hundred sixty thousand, seven hundred seventy-nine".