199717706385 has 24 divisors (see below), whose sum is σ = 346188908520. Its totient is φ = 106512556032.

The previous prime is 199717706291. The next prime is 199717706387. The reversal of 199717706385 is 583607717991.

It can be written as a sum of positive squares in 4 ways, for example, as 31533235776 + 168184470609 = 177576^2 + 410103^2 .

It is not a de Polignac number, because 199717706385 - 2²⁸ = 199449270929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (199717706387) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1824627 + ... + 1930983.

It is an arithmetic number, because the mean of its divisors is an integer number (14424537855).

Almost surely, 2^199717706385 is an apocalyptic number.

199717706385 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

199717706385 is a deficient number, since it is larger than the sum of its proper divisors (146471202135).

199717706385 is a wasteful number, since it uses less digits than its factorization.

199717706385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148097 (or 148094 counting only the distinct ones).

The product of its (nonzero) digits is 20003760, while the sum is 63.

The spelling of 199717706385 in words is "one hundred ninety-nine billion, seven hundred seventeen million, seven hundred six thousand, three hundred eighty-five".