688361520 has 240 divisors, whose sum is σ = 2674328832. Its totient is φ = 142295040.

The previous prime is 688361519. The next prime is 688361573. The reversal of 688361520 is 25163886.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (240).

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, 3566544 + ... + 3566736.

Almost surely, 2^688361520 is an apocalyptic number.

688361520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 688361520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1337164416).

688361520 is an abundant number, since it is smaller than the sum of its proper divisors (1985967312).

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

688361520 is a wasteful number, since it uses less digits than its factorization.

688361520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420 (or 221 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 39.

The square root of 688361520 is about 26236.6446025402. The cubic root of 688361520 is about 882.9555924547.

The spelling of 688361520 in words is "six hundred eighty-eight million, three hundred sixty-one thousand, five hundred twenty".