18387225 has 36 divisors (see below), whose sum is σ = 33426432. Its totient is φ = 9660000.

The previous prime is 18387221. The next prime is 18387233. The reversal of 18387225 is 52278381.

It is not a de Polignac number, because 18387225 - 2² = 18387221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18387225.

It is not an unprimeable number, because it can be changed into a prime (18387221) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 15400 + ... + 16550.

It is an arithmetic number, because the mean of its divisors is an integer number (928512).

Almost surely, 2^18387225 is an apocalyptic number.

18387225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18387225 is a deficient number, since it is larger than the sum of its proper divisors (15039207).

18387225 is a wasteful number, since it uses less digits than its factorization.

18387225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1238 (or 1230 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 18387225 is about 4288.0327657330. The cubic root of 18387225 is about 263.9401121043.

The spelling of 18387225 in words is "eighteen million, three hundred eighty-seven thousand, two hundred twenty-five".