688485122 has 16 divisors (see below), whose sum is σ = 1142228472. Its totient is φ = 309173760.

The previous prime is 688485113. The next prime is 688485137. The reversal of 688485122 is 221584886.

It is a Cunningham number, because it is equal to 26239²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 616082041 + 72403081 = 24821^2 + 8509^2 .

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 356879 + ... + 358802.

Almost surely, 2^688485122 is an apocalyptic number.

688485122 is a deficient number, since it is larger than the sum of its proper divisors (453743350).

688485122 is a wasteful number, since it uses less digits than its factorization.

688485122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 715733.

The product of its digits is 245760, while the sum is 44.

The square root of 688485122 is about 26239.0000190556. Note that the first 4 decimals coincide. The cubic root of 688485122 is about 883.0084370441.

The spelling of 688485122 in words is "six hundred eighty-eight million, four hundred eighty-five thousand, one hundred twenty-two".