199509601 has 2 divisors, whose sum is σ = 199509602. Its totient is φ = 199509600.

The previous prime is 199509593. The next prime is 199509631. The reversal of 199509601 is 106905991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196700625 + 2808976 = 14025^2 + 1676^2 .

It is an emirp because it is prime and its reverse (106905991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199509601 - 2³ = 199509593 is a prime.

It is not a weakly prime, because it can be changed into another prime (199509631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99754800 + 99754801.

It is an arithmetic number, because the mean of its divisors is an integer number (99754801).

Almost surely, 2^199509601 is an apocalyptic number.

It is an amenable number.

199509601 is a deficient number, since it is larger than the sum of its proper divisors (1).

199509601 is an equidigital number, since it uses as much as digits as its factorization.

199509601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21870, while the sum is 40.

The square root of 199509601 is about 14124.7867594523. The cubic root of 199509601 is about 584.3251779843.

The spelling of 199509601 in words is "one hundred ninety-nine million, five hundred nine thousand, six hundred one".