1311643 has 2 divisors, whose sum is σ = 1311644. Its totient is φ = 1311642.

The previous prime is 1311623. The next prime is 1311689. The reversal of 1311643 is 3461131.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1311643 - 2⁹ = 1311131 is a prime.

1311643 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311643.

It is not a weakly prime, because it can be changed into another prime (1311623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655821 + 655822.

It is an arithmetic number, because the mean of its divisors is an integer number (655822).

2^1311643 is an apocalyptic number.

1311643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311643 is an equidigital number, since it uses as much as digits as its factorization.

1311643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 216, while the sum is 19.

The square root of 1311643 is about 1145.2698372000. The cubic root of 1311643 is about 109.4641431632.

Adding to 1311643 its reverse (3461131), we get a palindrome (4772774).

The spelling of 1311643 in words is "one million, three hundred eleven thousand, six hundred forty-three".