57681 has 24 divisors (see below), whose sum is σ = 98280. Its totient is φ = 32256.

The previous prime is 57679. The next prime is 57689. The reversal of 57681 is 18675.

57681 = 34² + 35² + ... + 59².

It can be written as a sum of positive squares in 4 ways, for example, as 7056 + 50625 = 84^2 + 225^2 .

It is not a de Polignac number, because 57681 - 2¹ = 57679 is a prime.

It is a super-2 number, since 2×57681² = 6654195522, which contains 22 as substring.

It is a Curzon number.

It is a nialpdrome in base 9.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 57681.

It is not an unprimeable number, because it can be changed into a prime (57689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1975 + ... + 2003.

It is an arithmetic number, because the mean of its divisors is an integer number (4095).

2⁵⁷⁶⁸¹ is an apocalyptic number.

57681 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

57681 is a deficient number, since it is larger than the sum of its proper divisors (40599).

57681 is a wasteful number, since it uses less digits than its factorization.

57681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65 (or 62 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 57681 is about 240.1686907155. The cubic root of 57681 is about 38.6376698311.

It can be divided in two parts, 576 and 81, that multiplied together give a 6-th power (46656 = 6⁶).

The spelling of 57681 in words is "fifty-seven thousand, six hundred eighty-one".