199820717 has 4 divisors (see below), whose sum is σ = 199850460. Its totient is φ = 199790976.

The previous prime is 199820713. The next prime is 199820773. The reversal of 199820717 is 717028991.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 11417641 + 188403076 = 3379^2 + 13726^2 .

It is a cyclic number.

It is not a de Polignac number, because 199820717 - 2² = 199820713 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 (199820713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 509 + ... + 19997.

It is an arithmetic number, because the mean of its divisors is an integer number (49962615).

Almost surely, 2^199820717 is an apocalyptic number.

It is an amenable number.

199820717 is a deficient number, since it is larger than the sum of its proper divisors (29743).

199820717 is a wasteful number, since it uses less digits than its factorization.

199820717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29742.

The product of its (nonzero) digits is 63504, while the sum is 44.

The square root of 199820717 is about 14135.7955913348. The cubic root of 199820717 is about 584.6287531787.

The spelling of 199820717 in words is "one hundred ninety-nine million, eight hundred twenty thousand, seven hundred seventeen".