12427991 has 2 divisors, whose sum is σ = 12427992. Its totient is φ = 12427990.

The previous prime is 12427951. The next prime is 12427997. The reversal of 12427991 is 19972421.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12427991 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12427997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6213995 + 6213996.

It is an arithmetic number, because the mean of its divisors is an integer number (6213996).

Almost surely, 2^12427991 is an apocalyptic number.

12427991 is a deficient number, since it is larger than the sum of its proper divisors (1).

12427991 is an equidigital number, since it uses as much as digits as its factorization.

12427991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 12427991 is about 3525.3355868626. The cubic root of 12427991 is about 231.6329349527.

The spelling of 12427991 in words is "twelve million, four hundred twenty-seven thousand, nine hundred ninety-one".