218481285 has 32 divisors (see below), whose sum is σ = 401425920. Its totient is φ = 100353600.

The previous prime is 218481259. The next prime is 218481287. The reversal of 218481285 is 582184812.

It is not a de Polignac number, because 218481285 - 2⁵ = 218481253 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218481287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31711 + ... + 37980.

It is an arithmetic number, because the mean of its divisors is an integer number (12544560).

Almost surely, 2^218481285 is an apocalyptic number.

It is an amenable number.

218481285 is a deficient number, since it is larger than the sum of its proper divisors (182944635).

218481285 is a wasteful number, since it uses less digits than its factorization.

218481285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69729.

The product of its digits is 40960, while the sum is 39.

The square root of 218481285 is about 14781.1124412204. The cubic root of 218481285 is about 602.2887444249.

The spelling of 218481285 in words is "two hundred eighteen million, four hundred eighty-one thousand, two hundred eighty-five".