681589 has 2 divisors, whose sum is σ = 681590. Its totient is φ = 681588.

The previous prime is 681563. The next prime is 681607. The reversal of 681589 is 985186.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 400689 + 280900 = 633^2 + 530^2 .

It is a cyclic number.

It is not a de Polignac number, because 681589 - 2⁵ = 681557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (681539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340794 + 340795.

It is an arithmetic number, because the mean of its divisors is an integer number (340795).

2⁶⁸¹⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

681589 is a deficient number, since it is larger than the sum of its proper divisors (1).

681589 is an equidigital number, since it uses as much as digits as its factorization.

681589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 37.

The square root of 681589 is about 825.5840356984. The cubic root of 681589 is about 88.0050358688.

The spelling of 681589 in words is "six hundred eighty-one thousand, five hundred eighty-nine".