688513761 has 24 divisors (see below), whose sum is σ = 1073916480. Its totient is φ = 422555616.

The previous prime is 688513741. The next prime is 688513769. The reversal of 688513761 is 167315886.

688513761 is a `hidden beast` number, since 68 + 8 + 513 + 76 + 1 = 666.

It is not a de Polignac number, because 688513761 - 2⁵ = 688513729 is a prime.

It is not an unprimeable number, because it can be changed into a prime (688513769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36580 + ... + 52106.

It is an arithmetic number, because the mean of its divisors is an integer number (44746520).

Almost surely, 2^688513761 is an apocalyptic number.

It is an amenable number.

688513761 is a deficient number, since it is larger than the sum of its proper divisors (385402719).

688513761 is a wasteful number, since it uses less digits than its factorization.

688513761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15925 (or 15922 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 688513761 is about 26239.5457468303. The cubic root of 688513761 is about 883.0206804111.

The spelling of 688513761 in words is "six hundred eighty-eight million, five hundred thirteen thousand, seven hundred sixty-one".