172423205 has 4 divisors (see below), whose sum is σ = 206907852. Its totient is φ = 137938560.

The previous prime is 172423189. The next prime is 172423211. The reversal of 172423205 is 502324271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 102232321 + 70190884 = 10111^2 + 8378^2 .

It is not a de Polignac number, because 172423205 - 2⁴ = 172423189 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17242316 + ... + 17242325.

It is an arithmetic number, because the mean of its divisors is an integer number (51726963).

Almost surely, 2^172423205 is an apocalyptic number.

It is an amenable number.

172423205 is a deficient number, since it is larger than the sum of its proper divisors (34484647).

172423205 is an equidigital number, since it uses as much as digits as its factorization.

172423205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34484646.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 172423205 is about 13131.0016754245. The cubic root of 172423205 is about 556.5855210981.

Adding to 172423205 its reverse (502324271), we get a palindrome (674747476).

The spelling of 172423205 in words is "one hundred seventy-two million, four hundred twenty-three thousand, two hundred five".