12780517 has 2 divisors, whose sum is σ = 12780518. Its totient is φ = 12780516.

The previous prime is 12780511. The next prime is 12780527. The reversal of 12780517 is 71508721.

It is a happy number.

12780517 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9572836 + 3207681 = 3094^2 + 1791^2 .

It is an emirp because it is prime and its reverse (71508721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12780517 - 2²³ = 4391909 is a prime.

It is a super-2 number, since 2×12780517² = 326683229574578, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12780511) 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, 6390258 + 6390259.

It is an arithmetic number, because the mean of its divisors is an integer number (6390259).

Almost surely, 2^12780517 is an apocalyptic number.

It is an amenable number.

12780517 is a deficient number, since it is larger than the sum of its proper divisors (1).

12780517 is an equidigital number, since it uses as much as digits as its factorization.

12780517 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3920, while the sum is 31.

The square root of 12780517 is about 3574.9848950730. The cubic root of 12780517 is about 233.8026741274.

The spelling of 12780517 in words is "twelve million, seven hundred eighty thousand, five hundred seventeen".