172605 has 16 divisors (see below), whose sum is σ = 284544. Its totient is φ = 89280.

The previous prime is 172603. The next prime is 172607. The reversal of 172605 is 506271.

172605 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (172603) and next prime (172607).

It is not a de Polignac number, because 172605 - 2¹ = 172603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172603) 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, 400 + ... + 710.

It is an arithmetic number, because the mean of its divisors is an integer number (17784).

2¹⁷²⁶⁰⁵ is an apocalyptic number.

172605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

172605 is a deficient number, since it is larger than the sum of its proper divisors (111939).

172605 is a wasteful number, since it uses less digits than its factorization.

172605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 172605 is about 415.4575790619. The cubic root of 172605 is about 55.6781065010.

Adding to 172605 its reverse (506271), we get a palindrome (678876).

It can be divided in two parts, 172 and 605, that added together give a palindrome (777).

The spelling of 172605 in words is "one hundred seventy-two thousand, six hundred five".