1311288643 has 4 divisors (see below), whose sum is σ = 1498615600. Its totient is φ = 1123961688.

The previous prime is 1311288631. The next prime is 1311288653. The reversal of 1311288643 is 3468821131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1311288643 - 2⁵ = 1311288611 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311288613) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93663468 + ... + 93663481.

It is an arithmetic number, because the mean of its divisors is an integer number (374653900).

Almost surely, 2^1311288643 is an apocalyptic number.

1311288643 is a deficient number, since it is larger than the sum of its proper divisors (187326957).

1311288643 is an equidigital number, since it uses as much as digits as its factorization.

1311288643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187326956.

The product of its digits is 27648, while the sum is 37.

The square root of 1311288643 is about 36211.7196912823. The cubic root of 1311288643 is about 1094.5428456630.

The spelling of 1311288643 in words is "one billion, three hundred eleven million, two hundred eighty-eight thousand, six hundred forty-three".