20645385579 has 48 divisors (see below), whose sum is σ = 38634668800. Its totient is φ = 10316714688.

The previous prime is 20645385577. The next prime is 20645385589. The reversal of 20645385579 is 97558354602.

20645385579 is a `hidden beast` number, since 2 + 0 + 64 + 5 + 3 + 8 + 5 + 579 = 666.

It is not a de Polignac number, because 20645385579 - 2¹ = 20645385577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20645385577) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 647809 + ... + 678930.

Almost surely, 2^20645385579 is an apocalyptic number.

20645385579 is a deficient number, since it is larger than the sum of its proper divisors (17989283221).

20645385579 is a wasteful number, since it uses less digits than its factorization.

20645385579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1326784 (or 1326781 counting only the distinct ones).

The product of its (nonzero) digits is 9072000, while the sum is 54.

The spelling of 20645385579 in words is "twenty billion, six hundred forty-five million, three hundred eighty-five thousand, five hundred seventy-nine".