218994720 has 144 divisors (see below), whose sum is σ = 802545408. Its totient is φ = 50050560.

The previous prime is 218994719. The next prime is 218994751. The reversal of 218994720 is 27499812.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18865 + ... + 28175.

It is an arithmetic number, because the mean of its divisors is an integer number (5573232).

Almost surely, 2^218994720 is an apocalyptic number.

218994720 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 218994720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401272704).

218994720 is an abundant number, since it is smaller than the sum of its proper divisors (583550688).

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

218994720 is a wasteful number, since it uses less digits than its factorization.

218994720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9343 (or 9328 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 218994720 is about 14798.4701912056. The cubic root of 218994720 is about 602.7601718371.

The spelling of 218994720 in words is "two hundred eighteen million, nine hundred ninety-four thousand, seven hundred twenty".