688681387597 has 4 divisors (see below), whose sum is σ = 787064442976. Its totient is φ = 590298332220.

The previous prime is 688681387549. The next prime is 688681387609. The reversal of 688681387597 is 795783186886.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 795783186886 = 2 ⋅397891593443.

It is a cyclic number.

It is not a de Polignac number, because 688681387597 - 2³⁵ = 654321649229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688681387547) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49191527679 + ... + 49191527692.

It is an arithmetic number, because the mean of its divisors is an integer number (196766110744).

Almost surely, 2^688681387597 is an apocalyptic number.

It is an amenable number.

688681387597 is a deficient number, since it is larger than the sum of its proper divisors (98383055379).

688681387597 is an equidigital number, since it uses as much as digits as its factorization.

688681387597 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98383055378.

The product of its digits is 975421440, while the sum is 76.

The spelling of 688681387597 in words is "six hundred eighty-eight billion, six hundred eighty-one million, three hundred eighty-seven thousand, five hundred ninety-seven".