8172205 has 4 divisors (see below), whose sum is σ = 9806652. Its totient is φ = 6537760.

The previous prime is 8172181. The next prime is 8172209. The reversal of 8172205 is 5022718.

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 1297321 + 6874884 = 1139^2 + 2622^2 .

It is not a de Polignac number, because 8172205 - 2⁷ = 8172077 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8172205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8172209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 817216 + ... + 817225.

It is an arithmetic number, because the mean of its divisors is an integer number (2451663).

Almost surely, 2^8172205 is an apocalyptic number.

It is an amenable number.

8172205 is a deficient number, since it is larger than the sum of its proper divisors (1634447).

8172205 is a wasteful number, since it uses less digits than its factorization.

8172205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1634446.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 8172205 is about 2858.7068754946. The cubic root of 8172205 is about 201.4248663394.

The spelling of 8172205 in words is "eight million, one hundred seventy-two thousand, two hundred five".