40006 has 8 divisors (see below), whose sum is σ = 60984. Its totient is φ = 19680.

The previous prime is 39989. The next prime is 40009. The reversal of 40006 is 60004.

It is a sphenic number, since it is the product of 3 distinct primes.

40006 is a modest number, since divided by 6 gives 4 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 39974 and 40001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40009) 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 3 ways as a sum of consecutive naturals, for example, 46 + ... + 286.

It is an arithmetic number, because the mean of its divisors is an integer number (7623).

2⁴⁰⁰⁰⁶ is an apocalyptic number.

40006 is the 127-th centered pentagonal number.

40006 is a deficient number, since it is larger than the sum of its proper divisors (20978).

40006 is a wasteful number, since it uses less digits than its factorization.

40006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 40006 is about 200.0149994375. The cubic root of 40006 is about 34.2012288240.

The spelling of 40006 in words is "forty thousand, six", and thus it is an eban number.