218168225 has 48 divisors (see below), whose sum is σ = 326229120. Its totient is φ = 142771200.

The previous prime is 218168213. The next prime is 218168261. The reversal of 218168225 is 522861812.

It is a happy number.

It is not a de Polignac number, because 218168225 - 2¹⁴ = 218151841 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 106511 + ... + 108539.

It is an arithmetic number, because the mean of its divisors is an integer number (6796440).

Almost surely, 2^218168225 is an apocalyptic number.

218168225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

218168225 is a deficient number, since it is larger than the sum of its proper divisors (108060895).

218168225 is a wasteful number, since it uses less digits than its factorization.

218168225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2090 (or 2085 counting only the distinct ones).

The product of its digits is 15360, while the sum is 35.

The square root of 218168225 is about 14770.5187789732. The cubic root of 218168225 is about 602.0009354187. Note that the first 3 decimals are identical.

The spelling of 218168225 in words is "two hundred eighteen million, one hundred sixty-eight thousand, two hundred twenty-five".