18865789491456 has 432 divisors, whose sum is σ = 59479615104000. Its totient is φ = 5947448592384.

The previous prime is 18865789491449. The next prime is 18865789491503. The reversal of 18865789491456 is 65419498756881.

18865789491456 is a `hidden beast` number, since 1 + 8 + 8 + 6 + 5 + 7 + 89 + 491 + 45 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (81).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 707975925 + ... + 708002571.

Almost surely, 2^{18865789491456} is an apocalyptic number.

18865789491456 is a gapful number since it is divisible by the number (16) 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 18865789491456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29739807552000).

18865789491456 is an abundant number, since it is smaller than the sum of its proper divisors (40613825612544).

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

18865789491456 is an equidigital number, since it uses as much as digits as its factorization.

18865789491456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27296 (or 27270 counting only the distinct ones).

The product of its digits is 4180377600, while the sum is 81.

The spelling of 18865789491456 in words is "eighteen trillion, eight hundred sixty-five billion, seven hundred eighty-nine million, four hundred ninety-one thousand, four hundred fifty-six".