12172345 has 8 divisors (see below), whose sum is σ = 14625864. Its totient is φ = 9725184.

The previous prime is 12172333. The next prime is 12172361. The reversal of 12172345 is 54327121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5659641 + 6512704 = 2379^2 + 2552^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12172345 - 2⁹ = 12171833 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5547 + ... + 7423.

It is an arithmetic number, because the mean of its divisors is an integer number (1828233).

Almost surely, 2^12172345 is an apocalyptic number.

It is an amenable number.

12172345 is a deficient number, since it is larger than the sum of its proper divisors (2453519).

12172345 is a wasteful number, since it uses less digits than its factorization.

12172345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3179.

The product of its digits is 1680, while the sum is 25.

The square root of 12172345 is about 3488.8887915782. Note that the first 3 decimals coincide. The cubic root of 12172345 is about 230.0336749685.

Adding to 12172345 its reverse (54327121), we get a palindrome (66499466).

The spelling of 12172345 in words is "twelve million, one hundred seventy-two thousand, three hundred forty-five".