12806781 has 8 divisors (see below), whose sum is σ = 18389280. Its totient is φ = 7881072.

The previous prime is 12806749. The next prime is 12806861. The reversal of 12806781 is 18760821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12806781 - 2⁵ = 12806749 is a prime.

It is a super-2 number, since 2×12806781² = 328027279163922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12806881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 164151 + ... + 164228.

It is an arithmetic number, because the mean of its divisors is an integer number (2298660).

Almost surely, 2^12806781 is an apocalyptic number.

It is an amenable number.

12806781 is a deficient number, since it is larger than the sum of its proper divisors (5582499).

12806781 is a wasteful number, since it uses less digits than its factorization.

12806781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328395.

The product of its (nonzero) digits is 5376, while the sum is 33.

The square root of 12806781 is about 3578.6563120814. The cubic root of 12806781 is about 233.9627196069.

The spelling of 12806781 in words is "twelve million, eight hundred six thousand, seven hundred eighty-one".