20311801918218 has 128 divisors (see below), whose sum is σ = 48327806822400. Its totient is φ = 6304798684800.

The previous prime is 20311801918193. The next prime is 20311801918249. The reversal of 20311801918218 is 81281910811302.

20311801918218 is a `hidden beast` number, since 20 + 311 + 80 + 19 + 18 + 218 = 666.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 23690830 + ... + 24533222.

It is an arithmetic number, because the mean of its divisors is an integer number (377560990800).

Almost surely, 2^{20311801918218} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20311801918218, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24163903411200).

20311801918218 is an abundant number, since it is smaller than the sum of its proper divisors (28016004904182).

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

20311801918218 is a wasteful number, since it uses less digits than its factorization.

20311801918218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842825 (or 842819 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 45.

The spelling of 20311801918218 in words is "twenty trillion, three hundred eleven billion, eight hundred one million, nine hundred eighteen thousand, two hundred eighteen".