12778999 has 2 divisors, whose sum is σ = 12779000. Its totient is φ = 12778998.

The previous prime is 12778993. The next prime is 12779017. The reversal of 12778999 is 99987721.

It is a weak prime.

It is an emirp because it is prime and its reverse (99987721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12778999 - 2⁵ = 12778967 is a prime.

It is a plaindrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12778993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6389499 + 6389500.

It is an arithmetic number, because the mean of its divisors is an integer number (6389500).

Almost surely, 2^12778999 is an apocalyptic number.

12778999 is a deficient number, since it is larger than the sum of its proper divisors (1).

12778999 is an equidigital number, since it uses as much as digits as its factorization.

12778999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 571536, while the sum is 52.

The square root of 12778999 is about 3574.7725801791. The cubic root of 12778999 is about 233.7934171594.

The spelling of 12778999 in words is "twelve million, seven hundred seventy-eight thousand, nine hundred ninety-nine".