172218 has 8 divisors (see below), whose sum is σ = 344448. Its totient is φ = 57404.

The previous prime is 172217. The next prime is 172219. The reversal of 172218 is 812271.

172218 is nontrivially palindromic in base 15.

It is an interprime number because it is at equal distance from previous prime (172217) and next prime (172219).

It is a sphenic number, since it is the product of 3 distinct primes.

172218 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 172194 and 172203.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 172218.

It is not an unprimeable number, because it can be changed into a prime (172213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14346 + ... + 14357.

It is an arithmetic number, because the mean of its divisors is an integer number (43056).

2¹⁷²²¹⁸ is an apocalyptic number.

172218 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

172218 is a wasteful number, since it uses less digits than its factorization.

172218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28708.

The product of its digits is 224, while the sum is 21.

The square root of 172218 is about 414.9915661794. The cubic root of 172218 is about 55.6364631511.

Adding to 172218 its reverse (812271), we get a palindrome (984489).

The spelling of 172218 in words is "one hundred seventy-two thousand, two hundred eighteen".