12172817 has 2 divisors, whose sum is σ = 12172818. Its totient is φ = 12172816.

The previous prime is 12172813. The next prime is 12172841. The reversal of 12172817 is 71827121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9296401 + 2876416 = 3049^2 + 1696^2 .

It is a cyclic number.

It is not a de Polignac number, because 12172817 - 2² = 12172813 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12172817.

It is not a weakly prime, because it can be changed into another prime (12172813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6086408 + 6086409.

It is an arithmetic number, because the mean of its divisors is an integer number (6086409).

Almost surely, 2^12172817 is an apocalyptic number.

It is an amenable number.

12172817 is a deficient number, since it is larger than the sum of its proper divisors (1).

12172817 is an equidigital number, since it uses as much as digits as its factorization.

12172817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1568, while the sum is 29.

The square root of 12172817 is about 3488.9564342365. The cubic root of 12172817 is about 230.0366482244.

Adding to 12172817 its reverse (71827121), we get a palindrome (83999938).

The spelling of 12172817 in words is "twelve million, one hundred seventy-two thousand, eight hundred seventeen".