20108009 has 2 divisors, whose sum is σ = 20108010. Its totient is φ = 20108008.

The previous prime is 20107951. The next prime is 20108017. The reversal of 20108009 is 90080102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19333609 + 774400 = 4397^2 + 880^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20108009 is a prime.

It is not a weakly prime, because it can be changed into another prime (20108029) 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, 10054004 + 10054005.

It is an arithmetic number, because the mean of its divisors is an integer number (10054005).

Almost surely, 2^20108009 is an apocalyptic number.

It is an amenable number.

20108009 is a deficient number, since it is larger than the sum of its proper divisors (1).

20108009 is an equidigital number, since it uses as much as digits as its factorization.

20108009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 20108009 is about 4484.1954685317. The cubic root of 20108009 is about 271.9295205585.

The spelling of 20108009 in words is "twenty million, one hundred eight thousand, nine".