523681 has 2 divisors, whose sum is σ = 523682. Its totient is φ = 523680.

The previous prime is 523673. The next prime is 523717. The reversal of 523681 is 186325.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 512656 + 11025 = 716^2 + 105^2 .

It is a cyclic number.

It is not a de Polignac number, because 523681 - 2³ = 523673 is a prime.

It is a super-2 number, since 2×523681² = 548483579522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (523631) 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 as a sum of consecutive naturals, namely, 261840 + 261841.

It is an arithmetic number, because the mean of its divisors is an integer number (261841).

2⁵²³⁶⁸¹ is an apocalyptic number.

It is an amenable number.

523681 is a deficient number, since it is larger than the sum of its proper divisors (1).

523681 is an equidigital number, since it uses as much as digits as its factorization.

523681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

The square root of 523681 is about 723.6580684273. The cubic root of 523681 is about 80.6038165207.

The spelling of 523681 in words is "five hundred twenty-three thousand, six hundred eighty-one".