12781306 has 4 divisors (see below), whose sum is σ = 19171962. Its totient is φ = 6390652.

The previous prime is 12781303. The next prime is 12781313. The reversal of 12781306 is 60318721.

12781306 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 11799225 + 982081 = 3435^2 + 991^2 .

It is not an unprimeable number, because it can be changed into a prime (12781303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3195325 + ... + 3195328.

Almost surely, 2^12781306 is an apocalyptic number.

12781306 is a deficient number, since it is larger than the sum of its proper divisors (6390656).

12781306 is an equidigital number, since it uses as much as digits as its factorization.

12781306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6390655.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 12781306 is about 3575.0952434865. The cubic root of 12781306 is about 233.8074852659.

The spelling of 12781306 in words is "twelve million, seven hundred eighty-one thousand, three hundred six".