209798011 has 2 divisors, whose sum is σ = 209798012. Its totient is φ = 209798010.

The previous prime is 209797979. The next prime is 209798023. The reversal of 209798011 is 110897902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 209798011 - 2⁵ = 209797979 is a prime.

It is a super-2 number, since 2×209798011² = 88030410839112242, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (209798051) 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, 104899005 + 104899006.

It is an arithmetic number, because the mean of its divisors is an integer number (104899006).

Almost surely, 2^209798011 is an apocalyptic number.

209798011 is a deficient number, since it is larger than the sum of its proper divisors (1).

209798011 is an equidigital number, since it uses as much as digits as its factorization.

209798011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 209798011 is about 14484.4057869144. The cubic root of 209798011 is about 594.2015616267.

The spelling of 209798011 in words is "two hundred nine million, seven hundred ninety-eight thousand, eleven".