1331663 has 2 divisors, whose sum is σ = 1331664. Its totient is φ = 1331662.

The previous prime is 1331657. The next prime is 1331683. The reversal of 1331663 is 3661331.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1331663 - 2⁴ = 1331647 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331633) 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, 665831 + 665832.

It is an arithmetic number, because the mean of its divisors is an integer number (665832).

2^1331663 is an apocalyptic number.

1331663 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331663 is an equidigital number, since it uses as much as digits as its factorization.

1331663 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972, while the sum is 23.

The square root of 1331663 is about 1153.9770361667. The cubic root of 1331663 is about 110.0182614310.

Adding to 1331663 its reverse (3661331), we get a palindrome (4992994).

The spelling of 1331663 in words is "one million, three hundred thirty-one thousand, six hundred sixty-three".