12643856 has 10 divisors (see below), whose sum is σ = 24497502. Its totient is φ = 6321920.

The previous prime is 12643843. The next prime is 12643879. The reversal of 12643856 is 65834621.

It can be written as a sum of positive squares in only one way, i.e., 8317456 + 4326400 = 2884^2 + 2080^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 395105 + ... + 395136.

Almost surely, 2^12643856 is an apocalyptic number.

12643856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

12643856 is a deficient number, since it is larger than the sum of its proper divisors (11853646).

12643856 is an equidigital number, since it uses as much as digits as its factorization.

12643856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790249 (or 790243 counting only the distinct ones).

The product of its digits is 34560, while the sum is 35.

The square root of 12643856 is about 3555.8200179424. The cubic root of 12643856 is about 232.9663419119.

The spelling of 12643856 in words is "twelve million, six hundred forty-three thousand, eight hundred fifty-six".