218988 has 72 divisors (see below), whose sum is σ = 698880. Its totient is φ = 56160.

The previous prime is 218987. The next prime is 218989. The reversal of 218988 is 889812.

It is an interprime number because it is at equal distance from previous prime (218987) and next prime (218989).

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

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 218988.

It is not an unprimeable number, because it can be changed into a prime (218987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2733 + ... + 2811.

2²¹⁸⁹⁸⁸ is an apocalyptic number.

218988 is a gapful number since it is divisible by the number (28) 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 218988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349440).

218988 is an abundant number, since it is smaller than the sum of its proper divisors (479892).

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

218988 is a wasteful number, since it uses less digits than its factorization.

218988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107 (or 102 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 218988 is about 467.9615368810. The cubic root of 218988 is about 60.2754006407.

Adding to 218988 its sum of digits (36), we get a square (219024 = 468²).

It can be divided in two parts, 21 and 8988, that added together give a palindrome (9009).

The spelling of 218988 in words is "two hundred eighteen thousand, nine hundred eighty-eight".