218445844 has 12 divisors (see below), whose sum is σ = 382578868. Its totient is φ = 109137600.

The previous prime is 218445833. The next prime is 218445859. The reversal of 218445844 is 448544812.

It can be written as a sum of positive squares in 2 ways, for example, as 125708944 + 92736900 = 11212^2 + 9630^2 .

It is a junction number, because it is equal to n+sod(n) for n = 218445797 and 218445806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15387 + ... + 25954.

Almost surely, 2^218445844 is an apocalyptic number.

It is an amenable number.

218445844 is a deficient number, since it is larger than the sum of its proper divisors (164133024).

218445844 is a wasteful number, since it uses less digits than its factorization.

218445844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42666 (or 42664 counting only the distinct ones).

The product of its digits is 163840, while the sum is 40.

The square root of 218445844 is about 14779.9135315468. The cubic root of 218445844 is about 602.2561758539.

The spelling of 218445844 in words is "two hundred eighteen million, four hundred forty-five thousand, eight hundred forty-four".