218673664 has 80 divisors (see below), whose sum is σ = 488781216. Its totient is φ = 96870400.

The previous prime is 218673661. The next prime is 218673667. The reversal of 218673664 is 466376812.

It is an interprime number because it is at equal distance from previous prime (218673661) and next prime (218673667).

It is a self number, because there is not a number n which added to its sum of digits gives 218673664.

It is not an unprimeable number, because it can be changed into a prime (218673661) 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, 230439 + ... + 231385.

Almost surely, 2^218673664 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 218673664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244390608).

218673664 is an abundant number, since it is smaller than the sum of its proper divisors (270107552).

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

218673664 is an equidigital number, since it uses as much as digits as its factorization.

218673664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1017 (or 1001 counting only the distinct ones).

The product of its digits is 290304, while the sum is 43.

The square root of 218673664 is about 14787.6186047653. The cubic root of 218673664 is about 602.4654700343.

The spelling of 218673664 in words is "two hundred eighteen million, six hundred seventy-three thousand, six hundred sixty-four".