209159939 has 2 divisors, whose sum is σ = 209159940. Its totient is φ = 209159938.

The previous prime is 209159903. The next prime is 209159947. The reversal of 209159939 is 939951902.

209159939 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 209159939 - 2²⁰ = 208111363 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 209159893 and 209159902.

It is not a weakly prime, because it can be changed into another prime (209159989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104579969 + 104579970.

It is an arithmetic number, because the mean of its divisors is an integer number (104579970).

Almost surely, 2^209159939 is an apocalyptic number.

209159939 is a deficient number, since it is larger than the sum of its proper divisors (1).

209159939 is an equidigital number, since it uses as much as digits as its factorization.

209159939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 196830, while the sum is 47.

The square root of 209159939 is about 14462.3628429106. The cubic root of 209159939 is about 593.5985555913.

The spelling of 209159939 in words is "two hundred nine million, one hundred fifty-nine thousand, nine hundred thirty-nine".