218181072 has 80 divisors (see below), whose sum is σ = 579337920. Its totient is φ = 70726656.

The previous prime is 218181053. The next prime is 218181101. The reversal of 218181072 is 270181812.

It is a happy number.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 353308 + ... + 353924.

It is an arithmetic number, because the mean of its divisors is an integer number (7241724).

Almost surely, 2^218181072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218181072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289668960).

218181072 is an abundant number, since it is smaller than the sum of its proper divisors (361156848).

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

218181072 is a wasteful number, since it uses less digits than its factorization.

218181072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820 (or 814 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 30.

The square root of 218181072 is about 14770.9536591244. The cubic root of 218181072 is about 602.0127516127.

The spelling of 218181072 in words is "two hundred eighteen million, one hundred eighty-one thousand, seventy-two".