20009173 has 2 divisors, whose sum is σ = 20009174. Its totient is φ = 20009172.

The previous prime is 20009137. The next prime is 20009183. The reversal of 20009173 is 37190002.

Together with previous prime (20009137) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20007729 + 1444 = 4473^2 + 38^2 .

It is a cyclic number.

It is not a de Polignac number, because 20009173 - 2¹⁷ = 19878101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20009113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10004586 + 10004587.

It is an arithmetic number, because the mean of its divisors is an integer number (10004587).

Almost surely, 2^20009173 is an apocalyptic number.

It is an amenable number.

20009173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20009173 is an equidigital number, since it uses as much as digits as its factorization.

20009173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 378, while the sum is 22.

The square root of 20009173 is about 4473.1614100097. The cubic root of 20009173 is about 271.4832542379.

Adding to 20009173 its reverse (37190002), we get a palindrome (57199175).

The spelling of 20009173 in words is "twenty million, nine thousand, one hundred seventy-three".