209676139 has 2 divisors, whose sum is σ = 209676140. Its totient is φ = 209676138.

The previous prime is 209676121. The next prime is 209676161. The reversal of 209676139 is 931676902.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-209676139 is a prime.

It is a super-3 number, since 3×209676139³ (a number of 26 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 209676095 and 209676104.

It is not a weakly prime, because it can be changed into another prime (209676179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104838069 + 104838070.

It is an arithmetic number, because the mean of its divisors is an integer number (104838070).

Almost surely, 2^209676139 is an apocalyptic number.

209676139 is a deficient number, since it is larger than the sum of its proper divisors (1).

209676139 is an equidigital number, since it uses as much as digits as its factorization.

209676139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122472, while the sum is 43.

The square root of 209676139 is about 14480.1981685335. The cubic root of 209676139 is about 594.0864817947.

The spelling of 209676139 in words is "two hundred nine million, six hundred seventy-six thousand, one hundred thirty-nine".