1687377217 has 2 divisors, whose sum is σ = 1687377218. Its totient is φ = 1687377216.

The previous prime is 1687377203. The next prime is 1687377227. The reversal of 1687377217 is 7127737861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1417070736 + 270306481 = 37644^2 + 16441^2 .

It is an emirp because it is prime and its reverse (7127737861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1687377217 - 2¹⁹ = 1686852929 is a prime.

It is not a weakly prime, because it can be changed into another prime (1687377227) 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, 843688608 + 843688609.

It is an arithmetic number, because the mean of its divisors is an integer number (843688609).

Almost surely, 2^1687377217 is an apocalyptic number.

It is an amenable number.

1687377217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1687377217 is an equidigital number, since it uses as much as digits as its factorization.

1687377217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 691488, while the sum is 49.

The square root of 1687377217 is about 41077.6973186180. The cubic root of 1687377217 is about 1190.5219133331.

The spelling of 1687377217 in words is "one billion, six hundred eighty-seven million, three hundred seventy-seven thousand, two hundred seventeen".