20518163736 has 256 divisors, whose sum is σ = 63515612160. Its totient is φ = 5390745600.

The previous prime is 20518163713. The next prime is 20518163759. The reversal of 20518163736 is 63736181502.

It is an interprime number because it is at equal distance from previous prime (20518163713) and next prime (20518163759).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 23941420 + ... + 23942276.

It is an arithmetic number, because the mean of its divisors is an integer number (248107860).

Almost surely, 2^20518163736 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 20518163736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31757806080).

20518163736 is an abundant number, since it is smaller than the sum of its proper divisors (42997448424).

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

20518163736 is a wasteful number, since it uses less digits than its factorization.

20518163736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1074 (or 1070 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 42.

The spelling of 20518163736 in words is "twenty billion, five hundred eighteen million, one hundred sixty-three thousand, seven hundred thirty-six".