198997913717 has 4 divisors (see below), whose sum is σ = 198999807660. Its totient is φ = 198996019776.

The previous prime is 198997913677. The next prime is 198997913729. The reversal of 198997913717 is 717319799891.

198997913717 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 161624904676 + 37373009041 = 402026^2 + 193321^2 .

It is a cyclic number.

It is not a de Polignac number, because 198997913717 - 2¹⁰ = 198997912693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198997913747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 779492 + ... + 1002797.

It is an arithmetic number, because the mean of its divisors is an integer number (49749951915).

Almost surely, 2^198997913717 is an apocalyptic number.

It is an amenable number.

198997913717 is a deficient number, since it is larger than the sum of its proper divisors (1893943).

198997913717 is a wasteful number, since it uses less digits than its factorization.

198997913717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1893942.

The product of its digits is 54010152, while the sum is 71.

The spelling of 198997913717 in words is "one hundred ninety-eight billion, nine hundred ninety-seven million, nine hundred thirteen thousand, seven hundred seventeen".