18243540 has 72 divisors (see below), whose sum is σ = 63248640. Its totient is φ = 4169664.

The previous prime is 18243539. The next prime is 18243541. The reversal of 18243540 is 4534281.

18243540 is a `hidden beast` number, since 1 + 82 + 43 + 540 = 666.

It is an interprime number because it is at equal distance from previous prime (18243539) and next prime (18243541).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18243541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5980 + ... + 8499.

Almost surely, 2^18243540 is an apocalyptic number.

18243540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18243540 is an abundant number, since it is smaller than the sum of its proper divisors (45005100).

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

18243540 is a wasteful number, since it uses less digits than its factorization.

18243540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14501 (or 14496 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 18243540 is about 4271.2457199276. The cubic root of 18243540 is about 263.2508028861.

The spelling of 18243540 in words is "eighteen million, two hundred forty-three thousand, five hundred forty".