18509072 has 20 divisors (see below), whose sum is σ = 36193740. Its totient is φ = 9168768.

The previous prime is 18509069. The next prime is 18509093. The reversal of 18509072 is 27090581.

It can be written as a sum of positive squares in 2 ways, for example, as 16777216 + 1731856 = 4096^2 + 1316^2 .

It is a super-3 number, since 3×18509072³ (a number of 23 digits) contains 333 as substring.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3563 + ... + 7050.

It is an arithmetic number, because the mean of its divisors is an integer number (1809687).

Almost surely, 2^18509072 is an apocalyptic number.

It is an amenable number.

18509072 is a deficient number, since it is larger than the sum of its proper divisors (17684668).

18509072 is a wasteful number, since it uses less digits than its factorization.

18509072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10730 (or 10724 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 18509072 is about 4302.2171028436. The cubic root of 18509072 is about 264.5218481029.

The spelling of 18509072 in words is "eighteen million, five hundred nine thousand, seventy-two".