218243844 has 216 divisors, whose sum is σ = 715723008. Its totient is φ = 55520640.

The previous prime is 218243843. The next prime is 218243863. The reversal of 218243844 is 448342812.

218243844 is a `hidden beast` number, since 2 + 182 + 438 + 44 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 218243799 and 218243808.

It is not an unprimeable number, because it can be changed into a prime (218243843) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 710739 + ... + 711045.

Almost surely, 2^218243844 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218243844, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (357861504).

218243844 is an abundant number, since it is smaller than the sum of its proper divisors (497479164).

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

218243844 is a wasteful number, since it uses less digits than its factorization.

218243844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375 (or 363 counting only the distinct ones).

The product of its digits is 49152, while the sum is 36.

The square root of 218243844 is about 14773.0783521919. The cubic root of 218243844 is about 602.0704803004.

The spelling of 218243844 in words is "two hundred eighteen million, two hundred forty-three thousand, eight hundred forty-four".