20145173 has 2 divisors, whose sum is σ = 20145174. Its totient is φ = 20145172.

The previous prime is 20145163. The next prime is 20145193. The reversal of 20145173 is 37154102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14730244 + 5414929 = 3838^2 + 2327^2 .

It is a cyclic number.

It is not a de Polignac number, because 20145173 - 2⁶ = 20145109 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20145163) 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, 10072586 + 10072587.

It is an arithmetic number, because the mean of its divisors is an integer number (10072587).

Almost surely, 2^20145173 is an apocalyptic number.

It is an amenable number.

20145173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20145173 is an equidigital number, since it uses as much as digits as its factorization.

20145173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 20145173 is about 4488.3374427509. The cubic root of 20145173 is about 272.0969458708.

Adding to 20145173 its reverse (37154102), we get a palindrome (57299275).

The spelling of 20145173 in words is "twenty million, one hundred forty-five thousand, one hundred seventy-three".