18001040 has 40 divisors (see below), whose sum is σ = 42372288. Its totient is φ = 7111040.

The previous prime is 18001033. The next prime is 18001057. The reversal of 18001040 is 4010081.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5285 + ... + 7995.

Almost surely, 2^18001040 is an apocalyptic number.

18001040 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 18001040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21186144).

18001040 is an abundant number, since it is smaller than the sum of its proper divisors (24371248).

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

18001040 is a wasteful number, since it uses less digits than its factorization.

18001040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2807 (or 2801 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 18001040 is about 4242.7632505244. The cubic root of 18001040 is about 262.0791866775.

The spelling of 18001040 in words is "eighteen million, one thousand, forty".