218021328 has 160 divisors (see below), whose sum is σ = 757451520. Its totient is φ = 58613760.

The previous prime is 218021303. The next prime is 218021369. The reversal of 218021328 is 823120812.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 49288 + ... + 53528.

It is an arithmetic number, because the mean of its divisors is an integer number (4734072).

Almost surely, 2^218021328 is an apocalyptic number.

218021328 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 218021328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (378725760).

218021328 is an abundant number, since it is smaller than the sum of its proper divisors (539430192).

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

218021328 is a wasteful number, since it uses less digits than its factorization.

218021328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4282 (or 4270 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 218021328 is about 14765.5452997849. The cubic root of 218021328 is about 601.8657920195.

The spelling of 218021328 in words is "two hundred eighteen million, twenty-one thousand, three hundred twenty-eight".