688665058731 has 24 divisors (see below), whose sum is σ = 1071285598656. Its totient is φ = 423782472960.

The previous prime is 688665058727. The next prime is 688665058777. The reversal of 688665058731 is 137850566886.

It is a happy number.

688665058731 is a `hidden beast` number, since 68 + 8 + 66 + 505 + 8 + 7 + 3 + 1 = 666.

It is not a de Polignac number, because 688665058731 - 2² = 688665058727 is a prime.

It is a super-2 number, since 2×688665058731² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (688665058031) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6905086 + ... + 7004108.

It is an arithmetic number, because the mean of its divisors is an integer number (44636899944).

Almost surely, 2^688665058731 is an apocalyptic number.

688665058731 is a deficient number, since it is larger than the sum of its proper divisors (382620539925).

688665058731 is a wasteful number, since it uses less digits than its factorization.

688665058731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158483 (or 158480 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 63.

The spelling of 688665058731 in words is "six hundred eighty-eight billion, six hundred sixty-five million, fifty-eight thousand, seven hundred thirty-one".