18917203968 has 672 divisors, whose sum is σ = 66122312256. Its totient is φ = 5350883328.

The previous prime is 18917203939. The next prime is 18917203969. The reversal of 18917203968 is 86930271981.

18917203968 is a `hidden beast` number, since 1 + 89 + 172 + 0 + 396 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (18917203969) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 439934955 + ... + 439934997.

It is an arithmetic number, because the mean of its divisors is an integer number (98396298).

Almost surely, 2^18917203968 is an apocalyptic number.

18917203968 is a gapful number since it is divisible by the number (18) 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 18917203968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33061156128).

18917203968 is an abundant number, since it is smaller than the sum of its proper divisors (47205108288).

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

18917203968 is an equidigital number, since it uses as much as digits as its factorization.

18917203968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 54.

The spelling of 18917203968 in words is "eighteen billion, nine hundred seventeen million, two hundred three thousand, nine hundred sixty-eight".