12784861 has 4 divisors (see below), whose sum is σ = 12807900. Its totient is φ = 12761824.

The previous prime is 12784847. The next prime is 12784897. The reversal of 12784861 is 16848721.

12784861 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, and also an emirpimes, since its reverse is a distinct semiprime: 16848721 = 4057 ⋅4153.

It can be written as a sum of positive squares in 2 ways, for example, as 5788836 + 6996025 = 2406^2 + 2645^2 .

It is a cyclic number.

It is not a de Polignac number, because 12784861 - 2⁵ = 12784829 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12784861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12784831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10666 + ... + 11803.

It is an arithmetic number, because the mean of its divisors is an integer number (3201975).

Almost surely, 2^12784861 is an apocalyptic number.

It is an amenable number.

12784861 is a deficient number, since it is larger than the sum of its proper divisors (23039).

12784861 is an equidigital number, since it uses as much as digits as its factorization.

12784861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23038.

The product of its digits is 21504, while the sum is 37.

The square root of 12784861 is about 3575.5923984705. The cubic root of 12784861 is about 233.8291603738.

The spelling of 12784861 in words is "twelve million, seven hundred eighty-four thousand, eight hundred sixty-one".