1366681 has 6 divisors (see below), whose sum is σ = 1452110. Its totient is φ = 1286016.

The previous prime is 1366667. The next prime is 1366693. The reversal of 1366681 is 1866631.

It can be written as a sum of positive squares in 3 ways, for example, as 176400 + 1190281 = 420^2 + 1091^2 .

It is not a de Polignac number, because 1366681 - 2⁵ = 1366649 is a prime.

It is a super-2 number, since 2×1366681² = 3735633911522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1366601) 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 5 ways as a sum of consecutive naturals, for example, 2076 + ... + 2653.

2^1366681 is an apocalyptic number.

It is an amenable number.

1366681 is a deficient number, since it is larger than the sum of its proper divisors (85429).

1366681 is an equidigital number, since it uses as much as digits as its factorization.

1366681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4763 (or 4746 counting only the distinct ones).

The product of its digits is 5184, while the sum is 31.

The square root of 1366681 is about 1169.0513247929. The cubic root of 1366681 is about 110.9742926697.

The spelling of 1366681 in words is "one million, three hundred sixty-six thousand, six hundred eighty-one".