18518253408 has 144 divisors (see below), whose sum is σ = 57056375376. Its totient is φ = 5674475520.

The previous prime is 18518253401. The next prime is 18518253431. The reversal of 18518253408 is 80435281581.

18518253408 is a `hidden beast` number, since 18 + 5 + 182 + 53 + 408 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×18518253408² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18518253401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 166548 + ... + 254508.

It is an arithmetic number, because the mean of its divisors is an integer number (396224829).

Almost surely, 2^18518253408 is an apocalyptic number.

18518253408 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 18518253408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28528187688).

18518253408 is an abundant number, since it is smaller than the sum of its proper divisors (38538121968).

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

18518253408 is a wasteful number, since it uses less digits than its factorization.

18518253408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88037 (or 88026 counting only the distinct ones).

The product of its (nonzero) digits is 307200, while the sum is 45.

The spelling of 18518253408 in words is "eighteen billion, five hundred eighteen million, two hundred fifty-three thousand, four hundred eight".