1680366217 has 2 divisors, whose sum is σ = 1680366218. Its totient is φ = 1680366216.

The previous prime is 1680366187. The next prime is 1680366221. The reversal of 1680366217 is 7126630861.

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., 1261386256 + 418979961 = 35516^2 + 20469^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1680366217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1680366217.

It is not a weakly prime, because it can be changed into another prime (1680366257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840183108 + 840183109.

It is an arithmetic number, because the mean of its divisors is an integer number (840183109).

Almost surely, 2^1680366217 is an apocalyptic number.

It is an amenable number.

1680366217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680366217 is an equidigital number, since it uses as much as digits as its factorization.

1680366217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 1680366217 is about 40992.2702103701. The cubic root of 1680366217 is about 1188.8707638509.

The spelling of 1680366217 in words is "one billion, six hundred eighty million, three hundred sixty-six thousand, two hundred seventeen".