20057779640 has 32 divisors (see below), whose sum is σ = 45141295680. Its totient is φ = 8021104512.

The previous prime is 20057779639. The next prime is 20057779697. The reversal of 20057779640 is 4697775002.

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, 104657 + ... + 225983.

It is an arithmetic number, because the mean of its divisors is an integer number (1410665490).

Almost surely, 2^20057779640 is an apocalyptic number.

20057779640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20057779640 is an abundant number, since it is smaller than the sum of its proper divisors (25083516040).

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

20057779640 is a wasteful number, since it uses less digits than its factorization.

20057779640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125471 (or 125467 counting only the distinct ones).

The product of its (nonzero) digits is 740880, while the sum is 47.

The spelling of 20057779640 in words is "twenty billion, fifty-seven million, seven hundred seventy-nine thousand, six hundred forty".