199888935409 has 2 divisors, whose sum is σ = 199888935410. Its totient is φ = 199888935408.

The previous prime is 199888935403. The next prime is 199888935413. The reversal of 199888935409 is 904539888991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142602906384 + 57286029025 = 377628^2 + 239345^2 .

It is a cyclic number.

It is not a de Polignac number, because 199888935409 - 2³ = 199888935401 is a prime.

It is not a weakly prime, because it can be changed into another prime (199888935401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99944467704 + 99944467705.

It is an arithmetic number, because the mean of its divisors is an integer number (99944467705).

Almost surely, 2^199888935409 is an apocalyptic number.

It is an amenable number.

199888935409 is a deficient number, since it is larger than the sum of its proper divisors (1).

199888935409 is an equidigital number, since it uses as much as digits as its factorization.

199888935409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 201553920, while the sum is 73.

The spelling of 199888935409 in words is "one hundred ninety-nine billion, eight hundred eighty-eight million, nine hundred thirty-five thousand, four hundred nine".