688718836 has 12 divisors (see below), whose sum is σ = 1297970212. Its totient is φ = 317870208.

The previous prime is 688718827. The next prime is 688718837. The reversal of 688718836 is 638817886.

It can be written as a sum of positive squares in 2 ways, for example, as 187854436 + 500864400 = 13706^2 + 22380^2 .

It is a super-2 number, since 2×688718836² = 948667270122389792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688718837) 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 in 3 ways as a sum of consecutive naturals, for example, 6622245 + ... + 6622348.

Almost surely, 2^688718836 is an apocalyptic number.

It is an amenable number.

688718836 is a deficient number, since it is larger than the sum of its proper divisors (609251376).

688718836 is a wasteful number, since it uses less digits than its factorization.

688718836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13244610 (or 13244608 counting only the distinct ones).

The product of its digits is 3096576, while the sum is 55.

The square root of 688718836 is about 26243.4532026561. The cubic root of 688718836 is about 883.1083414477.

The spelling of 688718836 in words is "six hundred eighty-eight million, seven hundred eighteen thousand, eight hundred thirty-six".