12315997 has 4 divisors (see below), whose sum is σ = 12323196. Its totient is φ = 12308800.

The previous prime is 12315991. The next prime is 12316033. The reversal of 12315997 is 79951321.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 79951321 = 8317 ⋅9613.

It can be written as a sum of positive squares in 2 ways, for example, as 6095961 + 6220036 = 2469^2 + 2494^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12315997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12315991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 603 + ... + 4999.

It is an arithmetic number, because the mean of its divisors is an integer number (3080799).

Almost surely, 2^12315997 is an apocalyptic number.

It is an amenable number.

12315997 is a deficient number, since it is larger than the sum of its proper divisors (7199).

12315997 is an equidigital number, since it uses as much as digits as its factorization.

12315997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7198.

The product of its digits is 17010, while the sum is 37.

The square root of 12315997 is about 3509.4154783952. The cubic root of 12315997 is about 230.9350529233.

It can be divided in two parts, 123159 and 97, that added together give a triangular number (123256 = T₄₉₆).

The spelling of 12315997 in words is "twelve million, three hundred fifteen thousand, nine hundred ninety-seven".