688191012864 has 320 divisors, whose sum is σ = 2066235189480. Its totient is φ = 228261888000.

The previous prime is 688191012833. The next prime is 688191012953. The reversal of 688191012864 is 468210191886.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 688191012864.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 666205692 + ... + 666206724.

Almost surely, 2^688191012864 is an apocalyptic number.

688191012864 is a gapful number since it is divisible by the number (64) 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 688191012864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1033117594740).

688191012864 is an abundant number, since it is smaller than the sum of its proper divisors (1378044176616).

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

688191012864 is an equidigital number, since it uses as much as digits as its factorization.

688191012864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1326 (or 1289 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 54.

The spelling of 688191012864 in words is "six hundred eighty-eight billion, one hundred ninety-one million, twelve thousand, eight hundred sixty-four".