1243042313 has 2 divisors, whose sum is σ = 1243042314. Its totient is φ = 1243042312.

The previous prime is 1243042259. The next prime is 1243042349. The reversal of 1243042313 is 3132403421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1157904784 + 85137529 = 34028^2 + 9227^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243042313 - 2²⁶ = 1175933449 is a prime.

It is not a weakly prime, because it can be changed into another prime (1243042373) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621521156 + 621521157.

It is an arithmetic number, because the mean of its divisors is an integer number (621521157).

Almost surely, 2^1243042313 is an apocalyptic number.

It is an amenable number.

1243042313 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243042313 is an equidigital number, since it uses as much as digits as its factorization.

1243042313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 1243042313 is about 35256.8052012658. The cubic root of 1243042313 is about 1075.2149742780.

Adding to 1243042313 its reverse (3132403421), we get a palindrome (4375445734).

The spelling of 1243042313 in words is "one billion, two hundred forty-three million, forty-two thousand, three hundred thirteen".