2172305 has 4 divisors (see below), whose sum is σ = 2606772. Its totient is φ = 1737840.

The previous prime is 2172283. The next prime is 2172323. The reversal of 2172305 is 5032712.

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 654481 + 1517824 = 809^2 + 1232^2 .

It is not a de Polignac number, because 2172305 - 2⁶ = 2172241 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 217226 + ... + 217235.

It is an arithmetic number, because the mean of its divisors is an integer number (651693).

2^2172305 is an apocalyptic number.

It is an amenable number.

2172305 is a deficient number, since it is larger than the sum of its proper divisors (434467).

2172305 is an equidigital number, since it uses as much as digits as its factorization.

2172305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434466.

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 2172305 is about 1473.8741465946. The cubic root of 2172305 is about 129.5110826668.

The spelling of 2172305 in words is "two million, one hundred seventy-two thousand, three hundred five".