688799115607681 has 16 divisors (see below), whose sum is σ = 744993853110864. Its totient is φ = 633066933003264.

The previous prime is 688799115607679. The next prime is 688799115607777. The reversal of 688799115607681 is 186706511997886.

It can be written as a sum of positive squares in 8 ways, for example, as 59262914494081 + 629536201113600 = 7698241^2 + 25090560^2 .

It is a cyclic number.

It is not a de Polignac number, because 688799115607681 - 2¹ = 688799115607679 is a prime.

It is a super-2 number, since 2×688799115607681² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 688799115607595 and 688799115607604.

It is not an unprimeable number, because it can be changed into a prime (688799115607621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78243876 + ... + 86600821.

It is an arithmetic number, because the mean of its divisors is an integer number (46562115819429).

Almost surely, 2^{688799115607681} is an apocalyptic number.

It is an amenable number.

688799115607681 is a deficient number, since it is larger than the sum of its proper divisors (56194737503183).

688799115607681 is a wasteful number, since it uses less digits than its factorization.

688799115607681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164846100.

The product of its (nonzero) digits is 2194698240, while the sum is 82.

The spelling of 688799115607681 in words is "six hundred eighty-eight trillion, seven hundred ninety-nine billion, one hundred fifteen million, six hundred seven thousand, six hundred eighty-one".