12557779 has 4 divisors (see below), whose sum is σ = 13523776. Its totient is φ = 11591784.

The previous prime is 12557771. The next prime is 12557813. The reversal of 12557779 is 97775521.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12557779 - 2³ = 12557771 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (12557771) 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 in 3 ways as a sum of consecutive naturals, for example, 482979 + ... + 483004.

It is an arithmetic number, because the mean of its divisors is an integer number (3380944).

Almost surely, 2^12557779 is an apocalyptic number.

12557779 is a deficient number, since it is larger than the sum of its proper divisors (965997).

12557779 is an equidigital number, since it uses as much as digits as its factorization.

12557779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965996.

The product of its digits is 154350, while the sum is 43.

The square root of 12557779 is about 3543.6956697775. The cubic root of 12557779 is about 232.4364739535.

The spelling of 12557779 in words is "twelve million, five hundred fifty-seven thousand, seven hundred seventy-nine".