1312243421 has 2 divisors, whose sum is σ = 1312243422. Its totient is φ = 1312243420.

The previous prime is 1312243411. The next prime is 1312243463. The reversal of 1312243421 is 1243422131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1137712900 + 174530521 = 33730^2 + 13211^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1312243421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1312243411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656121710 + 656121711.

It is an arithmetic number, because the mean of its divisors is an integer number (656121711).

Almost surely, 2^1312243421 is an apocalyptic number.

It is an amenable number.

1312243421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1312243421 is an equidigital number, since it uses as much as digits as its factorization.

1312243421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 23.

The square root of 1312243421 is about 36224.9005657711. The cubic root of 1312243421 is about 1094.8084347578.

Adding to 1312243421 its reverse (1243422131), we get a palindrome (2555665552).

The spelling of 1312243421 in words is "one billion, three hundred twelve million, two hundred forty-three thousand, four hundred twenty-one".