18040240 has 20 divisors (see below), whose sum is σ = 41943744. Its totient is φ = 7216064.

The previous prime is 18040229. The next prime is 18040249. The reversal of 18040240 is 4204081.

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (18040249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112672 + ... + 112831.

Almost surely, 2^18040240 is an apocalyptic number.

18040240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18040240 is an abundant number, since it is smaller than the sum of its proper divisors (23903504).

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

18040240 is a wasteful number, since it uses less digits than its factorization.

18040240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225516 (or 225510 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 18040240 is about 4247.3803691217. The cubic root of 18040240 is about 262.2692878375.

The spelling of 18040240 in words is "eighteen million, forty thousand, two hundred forty".