18491128403904 has 1792 divisors, whose sum is σ = 66031676928000. Its totient is φ = 5021469573120.

The previous prime is 18491128403887. The next prime is 18491128403927. The reversal of 18491128403904 is 40930482119481.

18491128403904 is a `hidden beast` number, since 1 + 8 + 4 + 91 + 128 + 40 + 390 + 4 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 46577149434 + ... + 46577149830.

It is an arithmetic number, because the mean of its divisors is an integer number (36848034000).

Almost surely, 2^{18491128403904} 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 18491128403904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33015838464000).

18491128403904 is an abundant number, since it is smaller than the sum of its proper divisors (47540548524096).

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

18491128403904 is a wasteful number, since it uses less digits than its factorization.

18491128403904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 603 (or 587 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 54.

The spelling of 18491128403904 in words is "eighteen trillion, four hundred ninety-one billion, one hundred twenty-eight million, four hundred three thousand, nine hundred four".