2172505 has 4 divisors (see below), whose sum is σ = 2607012. Its totient is φ = 1738000.

The previous prime is 2172497. The next prime is 2172539. The reversal of 2172505 is 5052712.

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 1527696 + 644809 = 1236^2 + 803^2 .

It is not a de Polignac number, because 2172505 - 2³ = 2172497 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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, 217246 + ... + 217255.

It is an arithmetic number, because the mean of its divisors is an integer number (651753).

2^2172505 is an apocalyptic number.

It is an amenable number.

2172505 is a deficient number, since it is larger than the sum of its proper divisors (434507).

2172505 is an equidigital number, since it uses as much as digits as its factorization.

2172505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434506.

The product of its (nonzero) digits is 700, while the sum is 22.

The square root of 2172505 is about 1473.9419934312. The cubic root of 2172505 is about 129.5150571581.

The spelling of 2172505 in words is "two million, one hundred seventy-two thousand, five hundred five".