12391937 has 2 divisors, whose sum is σ = 12391938. Its totient is φ = 12391936.

The previous prime is 12391927. The next prime is 12391987. The reversal of 12391937 is 73919321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12117361 + 274576 = 3481^2 + 524^2 .

It is a cyclic number.

It is not a de Polignac number, because 12391937 - 2¹² = 12387841 is a prime.

It is a super-2 number, since 2×12391937² = 307120205223938, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 12391897 and 12391906.

It is not a weakly prime, because it can be changed into another prime (12391927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6195968 + 6195969.

It is an arithmetic number, because the mean of its divisors is an integer number (6195969).

Almost surely, 2^12391937 is an apocalyptic number.

It is an amenable number.

12391937 is a deficient number, since it is larger than the sum of its proper divisors (1).

12391937 is an equidigital number, since it uses as much as digits as its factorization.

12391937 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10206, while the sum is 35.

The square root of 12391937 is about 3520.2183170934. The cubic root of 12391937 is about 231.4087264793.

The spelling of 12391937 in words is "twelve million, three hundred ninety-one thousand, nine hundred thirty-seven".