1800045217 has 2 divisors, whose sum is σ = 1800045218. Its totient is φ = 1800045216.

The previous prime is 1800045133. The next prime is 1800045229. The reversal of 1800045217 is 7125400081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1787682961 + 12362256 = 42281^2 + 3516^2 .

It is an emirp because it is prime and its reverse (7125400081) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1800045217 is a prime.

It is not a weakly prime, because it can be changed into another prime (1800045917) 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, 900022608 + 900022609.

It is an arithmetic number, because the mean of its divisors is an integer number (900022609).

Almost surely, 2^1800045217 is an apocalyptic number.

It is an amenable number.

1800045217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1800045217 is an equidigital number, since it uses as much as digits as its factorization.

1800045217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 1800045217 is about 42426.9397553017. The cubic root of 1800045217 is about 1216.4505849156.

Adding to 1800045217 its reverse (7125400081), we get a palindrome (8925445298).

The spelling of 1800045217 in words is "one billion, eight hundred million, forty-five thousand, two hundred seventeen".