12780917 has 2 divisors, whose sum is σ = 12780918. Its totient is φ = 12780916.

The previous prime is 12780907. The next prime is 12780931. The reversal of 12780917 is 71908721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8994001 + 3786916 = 2999^2 + 1946^2 .

It is an emirp because it is prime and its reverse (71908721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12780917 - 2⁸ = 12780661 is a 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 (12780907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6390458 + 6390459.

It is an arithmetic number, because the mean of its divisors is an integer number (6390459).

Almost surely, 2^12780917 is an apocalyptic number.

It is an amenable number.

12780917 is a deficient number, since it is larger than the sum of its proper divisors (1).

12780917 is an equidigital number, since it uses as much as digits as its factorization.

12780917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 12780917 is about 3575.0408389276. The cubic root of 12780917 is about 233.8051132591.

The spelling of 12780917 in words is "twelve million, seven hundred eighty thousand, nine hundred seventeen".