18321312240 has 800 divisors, whose sum is σ = 80580842496. Its totient is φ = 3747409920.

The previous prime is 18321312209. The next prime is 18321312253. The reversal of 18321312240 is 4221312381.

18321312240 is a `hidden beast` number, since 1 + 8 + 321 + 312 + 24 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 36423829 + ... + 36424331.

Almost surely, 2^18321312240 is an apocalyptic number.

18321312240 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 18321312240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40290421248).

18321312240 is an abundant number, since it is smaller than the sum of its proper divisors (62259530256).

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

18321312240 is a wasteful number, since it uses less digits than its factorization.

18321312240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619 (or 604 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The spelling of 18321312240 in words is "eighteen billion, three hundred twenty-one million, three hundred twelve thousand, two hundred forty".