20518361136 has 720 divisors, whose sum is σ = 77362652640. Its totient is φ = 5016453120.

The previous prime is 20518361113. The next prime is 20518361161. The reversal of 20518361136 is 63116381502.

20518361136 is a `hidden beast` number, since 2 + 0 + 5 + 1 + 8 + 3 + 611 + 36 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20518361136.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 106312656 + ... + 106312848.

Almost surely, 2^20518361136 is an apocalyptic number.

20518361136 is a gapful number since it is divisible by the number (26) 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 20518361136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38681326320).

20518361136 is an abundant number, since it is smaller than the sum of its proper divisors (56844291504).

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

20518361136 is a wasteful number, since it uses less digits than its factorization.

20518361136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 20518361136 in words is "twenty billion, five hundred eighteen million, three hundred sixty-one thousand, one hundred thirty-six".