18918555289600 has 144 divisors (see below), whose sum is σ = 46944639296100. Its totient is φ = 7561279242240.

The previous prime is 18918555289547. The next prime is 18918555289607. The reversal of 18918555289600 is 698255581981.

It can be written as a sum of positive squares in 6 ways, for example, as 7183600690176 + 11734954599424 = 2680224^2 + 3425632^2 .

It is not an unprimeable number, because it can be changed into a prime (18918555289607) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63185046 + ... + 63483754.

Almost surely, 2^{18918555289600} is an apocalyptic number.

18918555289600 is a gapful number since it is divisible by the number (10) 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 18918555289600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23472319648050).

18918555289600 is an abundant number, since it is smaller than the sum of its proper divisors (28026084006500).

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

18918555289600 is a wasteful number, since it uses less digits than its factorization.

18918555289600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299978 (or 299953 counting only the distinct ones).

The product of its (nonzero) digits is 62208000, while the sum is 67.

The spelling of 18918555289600 in words is "eighteen trillion, nine hundred eighteen billion, five hundred fifty-five million, two hundred eighty-nine thousand, six hundred".