18312840 has 288 divisors, whose sum is σ = 75366720. Its totient is φ = 3773952.

The previous prime is 18312821. The next prime is 18312841. The reversal of 18312840 is 4821381.

It is not an unprimeable number, because it can be changed into a prime (18312841) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 425859 + ... + 425901.

It is an arithmetic number, because the mean of its divisors is an integer number (261690).

Almost surely, 2^18312840 is an apocalyptic number.

18312840 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 18312840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37683360).

18312840 is an abundant number, since it is smaller than the sum of its proper divisors (57053880).

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

18312840 is a wasteful number, since it uses less digits than its factorization.

18312840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 18312840 is about 4279.3504179957. The cubic root of 18312840 is about 263.5837103078.

The spelling of 18312840 in words is "eighteen million, three hundred twelve thousand, eight hundred forty".