18099440 has 40 divisors (see below), whose sum is σ = 42305328. Its totient is φ = 7201280.

The previous prime is 18099437. The next prime is 18099463. The reversal of 18099440 is 4499081.

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

It is a self number, because there is not a number n which added to its sum of digits gives 18099440.

It is a congruent number.

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, 18155 + ... + 19125.

Almost surely, 2^18099440 is an apocalyptic number.

18099440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18099440 is an abundant number, since it is smaller than the sum of its proper divisors (24205888).

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

18099440 is a wasteful number, since it uses less digits than its factorization.

18099440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1217 (or 1211 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 18099440 is about 4254.3436626582. The cubic root of 18099440 is about 262.5558581054. Note that the first 3 decimals are identical.

The spelling of 18099440 in words is "eighteen million, ninety-nine thousand, four hundred forty".