218436 has 24 divisors (see below), whose sum is σ = 517440. Its totient is φ = 71712.

The previous prime is 218423. The next prime is 218437. The reversal of 218436 is 634812.

It is a happy number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 218436.

It is not an unprimeable number, because it can be changed into a prime (218437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1225 + ... + 1391.

It is an arithmetic number, because the mean of its divisors is an integer number (21560).

2²¹⁸⁴³⁶ is an apocalyptic number.

It is an amenable number.

218436 is an abundant number, since it is smaller than the sum of its proper divisors (299004).

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

218436 is a wasteful number, since it uses less digits than its factorization.

218436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 281 counting only the distinct ones).

The product of its digits is 1152, while the sum is 24.

The square root of 218436 is about 467.3713726792. The cubic root of 218436 is about 60.2247129067.

The spelling of 218436 in words is "two hundred eighteen thousand, four hundred thirty-six".