185145217 has 4 divisors (see below), whose sum is σ = 189660996. Its totient is φ = 180629440.

The previous prime is 185145197. The next prime is 185145223. The reversal of 185145217 is 712541581.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 64496961 + 120648256 = 8031^2 + 10984^2 .

It is a cyclic number.

It is not a de Polignac number, because 185145217 - 2⁷ = 185145089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (185145617) 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 in 3 ways as a sum of consecutive naturals, for example, 2257828 + ... + 2257909.

It is an arithmetic number, because the mean of its divisors is an integer number (47415249).

Almost surely, 2^185145217 is an apocalyptic number.

It is an amenable number.

185145217 is a deficient number, since it is larger than the sum of its proper divisors (4515779).

185145217 is an equidigital number, since it uses as much as digits as its factorization.

185145217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4515778.

The product of its digits is 11200, while the sum is 34.

The square root of 185145217 is about 13606.8077446549. The cubic root of 185145217 is about 569.9509724939.

Adding to 185145217 its reverse (712541581), we get a palindrome (897686798).

The spelling of 185145217 in words is "one hundred eighty-five million, one hundred forty-five thousand, two hundred seventeen".