687457 has 2 divisors, whose sum is σ = 687458. Its totient is φ = 687456.

The previous prime is 687443. The next prime is 687461. The reversal of 687457 is 754786.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 421201 + 266256 = 649^2 + 516^2 .

It is a cyclic number.

It is not a de Polignac number, because 687457 - 2¹⁹ = 163169 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (687437) 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, 343728 + 343729.

It is an arithmetic number, because the mean of its divisors is an integer number (343729).

2⁶⁸⁷⁴⁵⁷ is an apocalyptic number.

It is an amenable number.

687457 is a deficient number, since it is larger than the sum of its proper divisors (1).

687457 is an equidigital number, since it uses as much as digits as its factorization.

687457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 37.

The square root of 687457 is about 829.1302672078. The cubic root of 687457 is about 88.2568682844.

The spelling of 687457 in words is "six hundred eighty-seven thousand, four hundred fifty-seven".