172221305 has 16 divisors (see below), whose sum is σ = 219490560. Its totient is φ = 129276672.

The previous prime is 172221299. The next prime is 172221323. The reversal of 172221305 is 503122271.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 172221305 - 2⁶ = 172221241 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26576 + ... + 32414.

It is an arithmetic number, because the mean of its divisors is an integer number (13718160).

Almost surely, 2^172221305 is an apocalyptic number.

It is an amenable number.

172221305 is a deficient number, since it is larger than the sum of its proper divisors (47269255).

172221305 is a wasteful number, since it uses less digits than its factorization.

172221305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6208.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 172221305 is about 13123.3115104382. The cubic root of 172221305 is about 556.3681905148.

Adding to 172221305 its reverse (503122271), we get a palindrome (675343576).

The spelling of 172221305 in words is "one hundred seventy-two million, two hundred twenty-one thousand, three hundred five".