20057817780 has 1728 divisors, whose sum is σ = 93694648320. Its totient is φ = 3527193600.

The previous prime is 20057817721. The next prime is 20057817809. The reversal of 20057817780 is 8771875002.

20057817780 is a `hidden beast` number, since 2 + 0 + 0 + 578 + 1 + 7 + 78 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 647026365 + ... + 647026395.

It is an arithmetic number, because the mean of its divisors is an integer number (54221440).

Almost surely, 2^20057817780 is an apocalyptic number.

20057817780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20057817780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46847324160).

20057817780 is an abundant number, since it is smaller than the sum of its proper divisors (73636830540).

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

20057817780 is a wasteful number, since it uses less digits than its factorization.

20057817780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 219520, while the sum is 45.

It can be divided in two parts, 2005781 and 7780, that added together give a square (2013561 = 1419²).

The spelling of 20057817780 in words is "twenty billion, fifty-seven million, eight hundred seventeen thousand, seven hundred eighty".