688911637680 has 320 divisors, whose sum is σ = 2715460485120. Its totient is φ = 157259142144.

The previous prime is 688911637669. The next prime is 688911637681. The reversal of 688911637680 is 86736119886.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (688911637681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11658289 + ... + 11717231.

It is an arithmetic number, because the mean of its divisors is an integer number (8485814016).

Almost surely, 2^688911637680 is an apocalyptic number.

688911637680 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 688911637680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1357730242560).

688911637680 is an abundant number, since it is smaller than the sum of its proper divisors (2026548847440).

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

688911637680 is a wasteful number, since it uses less digits than its factorization.

688911637680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59745 (or 59733 counting only the distinct ones).

The product of its (nonzero) digits is 20901888, while the sum is 63.

The spelling of 688911637680 in words is "six hundred eighty-eight billion, nine hundred eleven million, six hundred thirty-seven thousand, six hundred eighty".