18553561440 has 192 divisors, whose sum is σ = 59452081920. Its totient is φ = 4863006720.

The previous prime is 18553561373. The next prime is 18553561463. The reversal of 18553561440 is 4416535581.

It is a junction number, because it is equal to n+sod(n) for n = 18553561392 and 18553561401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6852567 + ... + 6855273.

It is an arithmetic number, because the mean of its divisors is an integer number (309646260).

Almost surely, 2^18553561440 is an apocalyptic number.

18553561440 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 18553561440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29726040960).

18553561440 is an abundant number, since it is smaller than the sum of its proper divisors (40898520480).

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

18553561440 is a wasteful number, since it uses less digits than its factorization.

18553561440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2965 (or 2957 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 42.

The spelling of 18553561440 in words is "eighteen billion, five hundred fifty-three million, five hundred sixty-one thousand, four hundred forty".