688555991760 has 640 divisors, whose sum is σ = 2779742085120. Its totient is φ = 136916656128.

The previous prime is 688555991749. The next prime is 688555991807. The reversal of 688555991760 is 67199555886.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 127 ways as a sum of consecutive naturals, for example, 81742909 + ... + 81751331.

It is an arithmetic number, because the mean of its divisors is an integer number (4343347008).

Almost surely, 2^688555991760 is an apocalyptic number.

688555991760 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 688555991760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1389871042560).

688555991760 is an abundant number, since it is smaller than the sum of its proper divisors (2091186093360).

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

688555991760 is a wasteful number, since it uses less digits than its factorization.

688555991760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8675 (or 8669 counting only the distinct ones).

The product of its (nonzero) digits is 163296000, while the sum is 69.

The spelling of 688555991760 in words is "six hundred eighty-eight billion, five hundred fifty-five million, nine hundred ninety-one thousand, seven hundred sixty".