688628986 has 8 divisors (see below), whose sum is σ = 1034527284. Its totient is φ = 343786560.

The previous prime is 688628981. The next prime is 688628987. The reversal of 688628986 is 689826886.

688628986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 609151761 + 79477225 = 24681^2 + 8915^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (688628981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262335 + ... + 264946.

Almost surely, 2^688628986 is an apocalyptic number.

688628986 is a deficient number, since it is larger than the sum of its proper divisors (345898298).

688628986 is a wasteful number, since it uses less digits than its factorization.

688628986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527936.

The product of its digits is 15925248, while the sum is 61.

The square root of 688628986 is about 26241.7412913092. The cubic root of 688628986 is about 883.0699364504.

The spelling of 688628986 in words is "six hundred eighty-eight million, six hundred twenty-eight thousand, nine hundred eighty-six".