688480656 has 80 divisors (see below), whose sum is σ = 1879046400. Its totient is φ = 216618624.

The previous prime is 688480631. The next prime is 688480657. The reversal of 688480656 is 656084886.

It is a super-2 number, since 2×688480656² = 948011227372380672, which contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 688480599 and 688480608.

It is not an unprimeable number, because it can be changed into a prime (688480657) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278755 + ... + 281213.

It is an arithmetic number, because the mean of its divisors is an integer number (23488080).

Almost surely, 2^688480656 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 688480656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (939523200).

688480656 is an abundant number, since it is smaller than the sum of its proper divisors (1190565744).

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

688480656 is a wasteful number, since it uses less digits than its factorization.

688480656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2796 (or 2790 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 51.

The square root of 688480656 is about 26238.9149165891. The cubic root of 688480656 is about 883.0065277682.

The spelling of 688480656 in words is "six hundred eighty-eight million, four hundred eighty thousand, six hundred fifty-six".