1243312313 has 4 divisors (see below), whose sum is σ = 1245975120. Its totient is φ = 1240649508.

The previous prime is 1243312297. The next prime is 1243312333. The reversal of 1243312313 is 3132133421.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1243312313 - 2⁴ = 1243312297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243312333) 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, 1330703 + ... + 1331636.

It is an arithmetic number, because the mean of its divisors is an integer number (311493780).

Almost surely, 2^1243312313 is an apocalyptic number.

It is an amenable number.

1243312313 is a deficient number, since it is larger than the sum of its proper divisors (2662807).

1243312313 is an equidigital number, since it uses as much as digits as its factorization.

1243312313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2662806.

The product of its digits is 1296, while the sum is 23.

The square root of 1243312313 is about 35260.6340413782. The cubic root of 1243312313 is about 1075.2928174384.

Adding to 1243312313 its reverse (3132133421), we get a palindrome (4375445734).

The spelling of 1243312313 in words is "one billion, two hundred forty-three million, three hundred twelve thousand, three hundred thirteen".