1231213393 has 2 divisors, whose sum is σ = 1231213394. Its totient is φ = 1231213392.

The previous prime is 1231213387. The next prime is 1231213411. The reversal of 1231213393 is 3933121321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 861305104 + 369908289 = 29348^2 + 19233^2 .

It is an emirp because it is prime and its reverse (3933121321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1231213393 - 2⁹ = 1231212881 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231213303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615606696 + 615606697.

It is an arithmetic number, because the mean of its divisors is an integer number (615606697).

Almost surely, 2^1231213393 is an apocalyptic number.

It is an amenable number.

1231213393 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231213393 is an equidigital number, since it uses as much as digits as its factorization.

1231213393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 28.

The square root of 1231213393 is about 35088.6504870165. The cubic root of 1231213393 is about 1071.7934789217.

The spelling of 1231213393 in words is "one billion, two hundred thirty-one million, two hundred thirteen thousand, three hundred ninety-three".