172218144 has 144 divisors (see below), whose sum is σ = 543303936. Its totient is φ = 47577600.

The previous prime is 172218127. The next prime is 172218149. The reversal of 172218144 is 441812271.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172218149) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 145234 + ... + 146414.

It is an arithmetic number, because the mean of its divisors is an integer number (3772944).

Almost surely, 2^172218144 is an apocalyptic number.

172218144 is a gapful number since it is divisible by the number (14) 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 172218144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271651968).

172218144 is an abundant number, since it is smaller than the sum of its proper divisors (371085792).

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

172218144 is a wasteful number, since it uses less digits than its factorization.

172218144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1239 (or 1224 counting only the distinct ones).

The product of its digits is 3584, while the sum is 30.

The square root of 172218144 is about 13123.1910753444. The cubic root of 172218144 is about 556.3647865793.

The spelling of 172218144 in words is "one hundred seventy-two million, two hundred eighteen thousand, one hundred forty-four".