218246820 has 96 divisors (see below), whose sum is σ = 688214016. Its totient is φ = 51196800.

The previous prime is 218246797. The next prime is 218246827. The reversal of 218246820 is 28642812.

It is a happy number.

It is a super-2 number, since 2×218246820² = 95263348880224800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (218246827) 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 31 ways as a sum of consecutive naturals, for example, 15127 + ... + 25793.

It is an arithmetic number, because the mean of its divisors is an integer number (7168896).

Almost surely, 2^218246820 is an apocalyptic number.

218246820 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 218246820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (344107008).

218246820 is an abundant number, since it is smaller than the sum of its proper divisors (469967196).

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

218246820 is a wasteful number, since it uses less digits than its factorization.

218246820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10721 (or 10719 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 218246820 is about 14773.1790756086. The cubic root of 218246820 is about 602.0732169238.

The spelling of 218246820 in words is "two hundred eighteen million, two hundred forty-six thousand, eight hundred twenty".