20394515620 has 24 divisors (see below), whose sum is σ = 43045894584. Its totient is φ = 8116394496.

The previous prime is 20394515573. The next prime is 20394515639. The reversal of 20394515620 is 2651549302.

It can be written as a sum of positive squares in 4 ways, for example, as 1947986496 + 18446529124 = 44136^2 + 135818^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20394515620.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2584197 + ... + 2592076.

It is an arithmetic number, because the mean of its divisors is an integer number (1793578941).

Almost surely, 2^20394515620 is an apocalyptic number.

20394515620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20394515620 is an abundant number, since it is smaller than the sum of its proper divisors (22651378964).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20394515620 is a wasteful number, since it uses less digits than its factorization.

20394515620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5176479 (or 5176477 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 37.

The spelling of 20394515620 in words is "twenty billion, three hundred ninety-four million, five hundred fifteen thousand, six hundred twenty".