20373209 has 2 divisors, whose sum is σ = 20373210. Its totient is φ = 20373208.

The previous prime is 20373203. The next prime is 20373211. The reversal of 20373209 is 90237302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14478025 + 5895184 = 3805^2 + 2428^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20373209 is a prime.

Together with 20373211, 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 (20373203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10186604 + 10186605.

It is an arithmetic number, because the mean of its divisors is an integer number (10186605).

Almost surely, 2^20373209 is an apocalyptic number.

It is an amenable number.

20373209 is a deficient number, since it is larger than the sum of its proper divisors (1).

20373209 is an equidigital number, since it uses as much as digits as its factorization.

20373209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 26.

The square root of 20373209 is about 4513.6691283256. The cubic root of 20373209 is about 273.1197755181.

The spelling of 20373209 in words is "twenty million, three hundred seventy-three thousand, two hundred nine".