40681 has 4 divisors (see below), whose sum is σ = 43092. Its totient is φ = 38272.

The previous prime is 40639. The next prime is 40693. The reversal of 40681 is 18604.

40681 is nontrivially palindromic in base 16.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13456 + 27225 = 116^2 + 165^2 .

It is a cyclic number.

It is not a de Polignac number, because 40681 - 2⁹ = 40169 is a prime.

It is a super-2 number, since 2×40681² = 3309887522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (41681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1180 + ... + 1213.

It is an arithmetic number, because the mean of its divisors is an integer number (10773).

2⁴⁰⁶⁸¹ is an apocalyptic number.

It is an amenable number.

40681 is a deficient number, since it is larger than the sum of its proper divisors (2411).

40681 is a wasteful number, since it uses less digits than its factorization.

40681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2410.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 40681 is about 201.6953147696. The cubic root of 40681 is about 34.3925100874.

The spelling of 40681 in words is "forty thousand, six hundred eighty-one".