12956509 has 2 divisors, whose sum is σ = 12956510. Its totient is φ = 12956508.

The previous prime is 12956497. The next prime is 12956563. The reversal of 12956509 is 90565921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11323225 + 1633284 = 3365^2 + 1278^2 .

It is a cyclic number.

It is not a de Polignac number, because 12956509 - 2⁵ = 12956477 is a prime.

It is a super-2 number, since 2×12956509² = 335742250934162, 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 (12956809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6478254 + 6478255.

It is an arithmetic number, because the mean of its divisors is an integer number (6478255).

Almost surely, 2^12956509 is an apocalyptic number.

It is an amenable number.

12956509 is a deficient number, since it is larger than the sum of its proper divisors (1).

12956509 is an equidigital number, since it uses as much as digits as its factorization.

12956509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24300, while the sum is 37.

The square root of 12956509 is about 3599.5151062331. The cubic root of 12956509 is about 234.8709658309.

The spelling of 12956509 in words is "twelve million, nine hundred fifty-six thousand, five hundred nine".