12644978 has 4 divisors (see below), whose sum is σ = 18967470. Its totient is φ = 6322488.

The previous prime is 12644941. The next prime is 12645011. The reversal of 12644978 is 87944621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87944621 = 17 ⋅5173213.

It can be written as a sum of positive squares in only one way, i.e., 12159169 + 485809 = 3487^2 + 697^2 .

It is an unprimeable number.

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, 3161243 + ... + 3161246.

Almost surely, 2^12644978 is an apocalyptic number.

12644978 is a deficient number, since it is larger than the sum of its proper divisors (6322492).

12644978 is an equidigital number, since it uses as much as digits as its factorization.

12644978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6322491.

The product of its digits is 96768, while the sum is 41.

The square root of 12644978 is about 3555.9777839576. The cubic root of 12644978 is about 232.9732327555.

The spelling of 12644978 in words is "twelve million, six hundred forty-four thousand, nine hundred seventy-eight".