1688888849 has 2 divisors, whose sum is σ = 1688888850. Its totient is φ = 1688888848.

The previous prime is 1688888819. The next prime is 1688888867. The reversal of 1688888849 is 9488888861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1641870400 + 47018449 = 40520^2 + 6857^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1688888849 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1688888819) 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, 844444424 + 844444425.

It is an arithmetic number, because the mean of its divisors is an integer number (844444425).

Almost surely, 2^1688888849 is an apocalyptic number.

It is an amenable number.

1688888849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688888849 is an equidigital number, since it uses as much as digits as its factorization.

1688888849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56623104, while the sum is 68.

The square root of 1688888849 is about 41096.0928678141. The cubic root of 1688888849 is about 1190.8773157632.

The spelling of 1688888849 in words is "one billion, six hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred forty-nine".