305680217 has 2 divisors, whose sum is σ = 305680218. Its totient is φ = 305680216.

The previous prime is 305680157. The next prime is 305680229. The reversal of 305680217 is 712086503.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 267289801 + 38390416 = 16349^2 + 6196^2 .

It is a cyclic number.

It is not a de Polignac number, because 305680217 - 2¹⁴ = 305663833 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (305686217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 152840108 + 152840109.

It is an arithmetic number, because the mean of its divisors is an integer number (152840109).

Almost surely, 2^305680217 is an apocalyptic number.

It is an amenable number.

305680217 is a deficient number, since it is larger than the sum of its proper divisors (1).

305680217 is an equidigital number, since it uses as much as digits as its factorization.

305680217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 305680217 is about 17483.7129065882. The cubic root of 305680217 is about 673.6315885864.

The spelling of 305680217 in words is "three hundred five million, six hundred eighty thousand, two hundred seventeen".