198931211393 has 2 divisors, whose sum is σ = 198931211394. Its totient is φ = 198931211392.

The previous prime is 198931211299. The next prime is 198931211411. The reversal of 198931211393 is 393112139891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198615509569 + 315701824 = 445663^2 + 17768^2 .

It is a cyclic number.

It is not a de Polignac number, because 198931211393 - 2¹⁴ = 198931195009 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (198931211593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99465605696 + 99465605697.

It is an arithmetic number, because the mean of its divisors is an integer number (99465605697).

Almost surely, 2^198931211393 is an apocalyptic number.

It is an amenable number.

198931211393 is a deficient number, since it is larger than the sum of its proper divisors (1).

198931211393 is an equidigital number, since it uses as much as digits as its factorization.

198931211393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 314928, while the sum is 50.

The spelling of 198931211393 in words is "one hundred ninety-eight billion, nine hundred thirty-one million, two hundred eleven thousand, three hundred ninety-three".