688811999 has 2 divisors, whose sum is σ = 688812000. Its totient is φ = 688811998.

The previous prime is 688811987. The next prime is 688812011. The reversal of 688811999 is 999118886.

It is a balanced prime because it is at equal distance from previous prime (688811987) and next prime (688812011).

It is a cyclic number.

It is not a de Polignac number, because 688811999 - 2⁴ = 688811983 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688811099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344405999 + 344406000.

It is an arithmetic number, because the mean of its divisors is an integer number (344406000).

Almost surely, 2^688811999 is an apocalyptic number.

688811999 is a deficient number, since it is larger than the sum of its proper divisors (1).

688811999 is an equidigital number, since it uses as much as digits as its factorization.

688811999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 59.

The square root of 688811999 is about 26245.2281186504. The cubic root of 688811999 is about 883.1481590088.

The spelling of 688811999 in words is "six hundred eighty-eight million, eight hundred eleven thousand, nine hundred ninety-nine".