20518840920 has 32 divisors (see below), whose sum is σ = 61556523120. Its totient is φ = 5471690880.

The previous prime is 20518840871. The next prime is 20518840957. The reversal of 20518840920 is 2904881502.

It is a congruent number.

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, 85495051 + ... + 85495290.

Almost surely, 2^20518840920 is an apocalyptic number.

20518840920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20518840920 is an abundant number, since it is smaller than the sum of its proper divisors (41037682200).

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

20518840920 is a wasteful number, since it uses less digits than its factorization.

20518840920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170990355 (or 170990351 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 39.

The spelling of 20518840920 in words is "twenty billion, five hundred eighteen million, eight hundred forty thousand, nine hundred twenty".