2109873209 has 2 divisors, whose sum is σ = 2109873210. Its totient is φ = 2109873208.

The previous prime is 2109873203. The next prime is 2109873211. The reversal of 2109873209 is 9023789012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1139737600 + 970135609 = 33760^2 + 31147^2 .

It is a cyclic number.

It is not a de Polignac number, because 2109873209 - 2⁸ = 2109872953 is a prime.

Together with 2109873211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2109873203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1054936604 + 1054936605.

It is an arithmetic number, because the mean of its divisors is an integer number (1054936605).

Almost surely, 2^2109873209 is an apocalyptic number.

It is an amenable number.

2109873209 is a deficient number, since it is larger than the sum of its proper divisors (1).

2109873209 is an equidigital number, since it uses as much as digits as its factorization.

2109873209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 2109873209 is about 45933.3561695637. The cubic root of 2109873209 is about 1282.5829209964.

The spelling of 2109873209 in words is "two billion, one hundred nine million, eight hundred seventy-three thousand, two hundred nine".