18251331840 has 864 divisors, whose sum is σ = 76527360000. Its totient is φ = 4010065920.

The previous prime is 18251331793. The next prime is 18251331863. The reversal of 18251331840 is 4813315281.

It is a super-2 number, since 2×18251331840² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18251331795 and 18251331804.

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 122492086 + ... + 122492234.

Almost surely, 2^18251331840 is an apocalyptic number.

18251331840 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 18251331840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38263680000).

18251331840 is an abundant number, since it is smaller than the sum of its proper divisors (58276028160).

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

18251331840 is a wasteful number, since it uses less digits than its factorization.

18251331840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 18251331840 in words is "eighteen billion, two hundred fifty-one million, three hundred thirty-one thousand, eight hundred forty".