681597 has 24 divisors (see below), whose sum is σ = 1164800. Its totient is φ = 375840.

The previous prime is 681589. The next prime is 681607. The reversal of 681597 is 795186.

681597 is a `hidden beast` number, since 68 + 1 + 597 = 666.

It is not a de Polignac number, because 681597 - 2³ = 681589 is a prime.

681597 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681557) 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, 1779 + ... + 2127.

2⁶⁸¹⁵⁹⁷ is an apocalyptic number.

It is an amenable number.

681597 is a deficient number, since it is larger than the sum of its proper divisors (483203).

681597 is a wasteful number, since it uses less digits than its factorization.

681597 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393 (or 390 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 681597 is about 825.5888807391. The cubic root of 681597 is about 88.0053801807.

The spelling of 681597 in words is "six hundred eighty-one thousand, five hundred ninety-seven".