18252009 has 12 divisors (see below), whose sum is σ = 26439556. Its totient is φ = 12133152.

The previous prime is 18252001. The next prime is 18252023. The reversal of 18252009 is 90025281.

It can be written as a sum of positive squares in 2 ways, for example, as 10112400 + 8139609 = 3180^2 + 2853^2 .

It is not a de Polignac number, because 18252009 - 2³ = 18252001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18252001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 639 + ... + 6075.

Almost surely, 2^18252009 is an apocalyptic number.

It is an amenable number.

18252009 is a deficient number, since it is larger than the sum of its proper divisors (8187547).

18252009 is a wasteful number, since it uses less digits than its factorization.

18252009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5816 (or 5813 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 18252009 is about 4272.2370018528. The cubic root of 18252009 is about 263.2915319359.

The spelling of 18252009 in words is "eighteen million, two hundred fifty-two thousand, nine".