21780919293579 has 32 divisors (see below), whose sum is σ = 32975066880000. Its totient is φ = 14202829714752.

The previous prime is 21780919293569. The next prime is 21780919293587. The reversal of 21780919293579 is 97539291908712.

21780919293579 is a `hidden beast` number, since 2 + 1 + 7 + 80 + 9 + 192 + 9 + 357 + 9 = 666.

It is not a de Polignac number, because 21780919293579 - 2⁴ = 21780919293563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21780919293559) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3291879 + ... + 7375520.

It is an arithmetic number, because the mean of its divisors is an integer number (1030470840000).

Almost surely, 2^{21780919293579} is an apocalyptic number.

21780919293579 is a deficient number, since it is larger than the sum of its proper divisors (11194147586421).

21780919293579 is a wasteful number, since it uses less digits than its factorization.

21780919293579 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10669064 (or 10669058 counting only the distinct ones).

The product of its (nonzero) digits is 154314720, while the sum is 72.

The spelling of 21780919293579 in words is "twenty-one trillion, seven hundred eighty billion, nine hundred nineteen million, two hundred ninety-three thousand, five hundred seventy-nine".