218959812 has 18 divisors (see below), whose sum is σ = 553481838. Its totient is φ = 72986592.

The previous prime is 218959799. The next prime is 218959823.

218959812 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 172501956 + 46457856 = 13134^2 + 6816^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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 5 ways as a sum of consecutive naturals, for example, 3041073 + ... + 3041144.

It is an arithmetic number, because the mean of its divisors is an integer number (30748991).

Almost surely, 2^218959812 is an apocalyptic number.

It is an amenable number.

218959812 is an abundant number, since it is smaller than the sum of its proper divisors (334522026).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218959812 is a wasteful number, since it uses less digits than its factorization.

218959812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6082227 (or 6082222 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The square root of 218959812 is about 14797.2906979622. The cubic root of 218959812 is about 602.7281432564.

It can be divided in two parts, 2189 and 59812, that added together give a square (62001 = 249²).

The spelling of 218959812 in words is "two hundred eighteen million, nine hundred fifty-nine thousand, eight hundred twelve".