198931211749 has 2 divisors, whose sum is σ = 198931211750. Its totient is φ = 198931211748.

The previous prime is 198931211723. The next prime is 198931211777. The reversal of 198931211749 is 947112139891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198543318724 + 387893025 = 445582^2 + 19695^2 .

It is a cyclic number.

It is not a de Polignac number, because 198931211749 - 2²⁷ = 198796994021 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198931211749.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198931211719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99465605874 + 99465605875.

It is an arithmetic number, because the mean of its divisors is an integer number (99465605875).

Almost surely, 2^198931211749 is an apocalyptic number.

It is an amenable number.

198931211749 is a deficient number, since it is larger than the sum of its proper divisors (1).

198931211749 is an equidigital number, since it uses as much as digits as its factorization.

198931211749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 979776, while the sum is 55.

The spelling of 198931211749 in words is "one hundred ninety-eight billion, nine hundred thirty-one million, two hundred eleven thousand, seven hundred forty-nine".