1366809 has 4 divisors (see below), whose sum is σ = 1822416. Its totient is φ = 911204.

The previous prime is 1366801. The next prime is 1366829. The reversal of 1366809 is 9086631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1366809 - 2³ = 1366801 is a prime.

It is a D-number.

1366809 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1366809.

It is not an unprimeable number, because it can be changed into a prime (1366801) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 227799 + ... + 227804.

It is an arithmetic number, because the mean of its divisors is an integer number (455604).

2^1366809 is an apocalyptic number.

It is an amenable number.

1366809 is a deficient number, since it is larger than the sum of its proper divisors (455607).

1366809 is an equidigital number, since it uses as much as digits as its factorization.

1366809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455606.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 1366809 is about 1169.1060687551. The cubic root of 1366809 is about 110.9777570884.

The spelling of 1366809 in words is "one million, three hundred sixty-six thousand, eight hundred nine".