688042836 has 144 divisors (see below), whose sum is σ = 2057275584. Its totient is φ = 199190016.

The previous prime is 688042829. The next prime is 688042843. The reversal of 688042836 is 638240886.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (688042829) and next prime (688042843).

It is a junction number, because it is equal to n+sod(n) for n = 688042791 and 688042800.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 213211 + ... + 216413.

It is an arithmetic number, because the mean of its divisors is an integer number (14286636).

Almost surely, 2^688042836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688042836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1028637792).

688042836 is an abundant number, since it is smaller than the sum of its proper divisors (1369232748).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688042836 is a wasteful number, since it uses less digits than its factorization.

688042836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3252 (or 3238 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The square root of 688042836 is about 26230.5706380933. The cubic root of 688042836 is about 882.8193136505.

The spelling of 688042836 in words is "six hundred eighty-eight million, forty-two thousand, eight hundred thirty-six".