20818775579 has 12 divisors (see below), whose sum is σ = 24314258808. Its totient is φ = 17773560000.

The previous prime is 20818775573. The next prime is 20818775587. The reversal of 20818775579 is 97557781802.

It is not a de Polignac number, because 20818775579 - 2¹² = 20818771483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20818775573) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 834062 + ... + 858659.

It is an arithmetic number, because the mean of its divisors is an integer number (2026188234).

Almost surely, 2^20818775579 is an apocalyptic number.

20818775579 is a deficient number, since it is larger than the sum of its proper divisors (3495483229).

20818775579 is a wasteful number, since it uses less digits than its factorization.

20818775579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1692986 (or 1692979 counting only the distinct ones).

The product of its (nonzero) digits is 9878400, while the sum is 59.

The spelling of 20818775579 in words is "twenty billion, eight hundred eighteen million, seven hundred seventy-five thousand, five hundred seventy-nine".