218128444 has 12 divisors (see below), whose sum is σ = 381843000. Its totient is φ = 109030448.

The previous prime is 218128439. The next prime is 218128489. The reversal of 218128444 is 444821812.

218128444 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×218128444² = 95160036163722272, which contains 22 as substring.

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, 11127 + ... + 23665.

It is an arithmetic number, because the mean of its divisors is an integer number (31820250).

Almost surely, 2^218128444 is an apocalyptic number.

It is an amenable number.

218128444 is a deficient number, since it is larger than the sum of its proper divisors (163714556).

218128444 is a wasteful number, since it uses less digits than its factorization.

218128444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16892 (or 16890 counting only the distinct ones).

The product of its digits is 16384, while the sum is 34.

The square root of 218128444 is about 14769.1720824155. The cubic root of 218128444 is about 601.9643433883.

It can be divided in two parts, 2181 and 28444, that added together give a square (30625 = 175²).

The spelling of 218128444 in words is "two hundred eighteen million, one hundred twenty-eight thousand, four hundred forty-four".