1366663 has 2 divisors, whose sum is σ = 1366664. Its totient is φ = 1366662.

The previous prime is 1366661. The next prime is 1366667. The reversal of 1366663 is 3666631.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1366663 - 2¹ = 1366661 is a prime.

Together with 1366661, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1366661) 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 as a sum of consecutive naturals, namely, 683331 + 683332.

It is an arithmetic number, because the mean of its divisors is an integer number (683332).

2^1366663 is an apocalyptic number.

1366663 is a deficient number, since it is larger than the sum of its proper divisors (1).

1366663 is an equidigital number, since it uses as much as digits as its factorization.

1366663 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 31.

The square root of 1366663 is about 1169.0436262176. The cubic root of 1366663 is about 110.9738054684.

Subtracting 1366663 from its reverse (3666631), we obtain a cube (2299968 = 132³).

The spelling of 1366663 in words is "one million, three hundred sixty-six thousand, six hundred sixty-three".