218812 has 12 divisors (see below), whose sum is σ = 417816. Its totient is φ = 99440.

The previous prime is 218809. The next prime is 218819.

218812 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218819) 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 3 ways as a sum of consecutive naturals, for example, 2443 + ... + 2530.

It is an arithmetic number, because the mean of its divisors is an integer number (34818).

2²¹⁸⁸¹² is an apocalyptic number.

218812 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

218812 is a deficient number, since it is larger than the sum of its proper divisors (199004).

218812 is a wasteful number, since it uses less digits than its factorization.

218812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4988 (or 4986 counting only the distinct ones).

The product of its digits is 256, while the sum is 22.

The square root of 218812 is about 467.7734494389. The cubic root of 218812 is about 60.2592485931.

The spelling of 218812 in words is "two hundred eighteen thousand, eight hundred twelve".