218171982 has 32 divisors (see below), whose sum is σ = 528014592. Its totient is φ = 58667904.

The previous prime is 218171977. The next prime is 218171983. The reversal of 218171982 is 289171812.

218171982 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 218171982.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218171983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152068 + ... + 153495.

It is an arithmetic number, because the mean of its divisors is an integer number (16500456).

Almost surely, 2^218171982 is an apocalyptic number.

218171982 is an abundant number, since it is smaller than the sum of its proper divisors (309842610).

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

218171982 is a wasteful number, since it uses less digits than its factorization.

218171982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305592.

The product of its digits is 16128, while the sum is 39.

The square root of 218171982 is about 14770.6459574387. The cubic root of 218171982 is about 602.0043910159.

The spelling of 218171982 in words is "two hundred eighteen million, one hundred seventy-one thousand, nine hundred eighty-two".