218638080 has 108 divisors (see below), whose sum is σ = 756504840. Its totient is φ = 58300416.

The previous prime is 218638067. The next prime is 218638087. The reversal of 218638080 is 80836812.

218638080 is a `hidden beast` number, since 2 + 18 + 638 + 0 + 8 + 0 = 666.

It is a super-2 number, since 2×218638080² = 95605220052172800, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218638087) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2031 + ... + 21009.

Almost surely, 2^218638080 is an apocalyptic number.

218638080 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218638080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (378252420).

218638080 is an abundant number, since it is smaller than the sum of its proper divisors (537866760).

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

218638080 is a wasteful number, since it uses less digits than its factorization.

218638080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19006 (or 18989 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 218638080 is about 14786.4153871045. The cubic root of 218638080 is about 602.4327892291.

The spelling of 218638080 in words is "two hundred eighteen million, six hundred thirty-eight thousand, eighty".