20518773912 has 288 divisors, whose sum is σ = 72022532400. Its totient is φ = 5224601088.

The previous prime is 20518773907. The next prime is 20518773953. The reversal of 20518773912 is 21937781502.

20518773912 is a `hidden beast` number, since 20 + 518 + 77 + 39 + 12 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1322343 + ... + 1337769.

Almost surely, 2^20518773912 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20518773912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36011266200).

20518773912 is an abundant number, since it is smaller than the sum of its proper divisors (51503758488).

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

20518773912 is a wasteful number, since it uses less digits than its factorization.

20518773912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15495 (or 15481 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 45.

It can be divided in two parts, 20518 and 773912, that added together give a triangular number (794430 = T₁₂₆₀).

The spelling of 20518773912 in words is "twenty billion, five hundred eighteen million, seven hundred seventy-three thousand, nine hundred twelve".