40004 has 12 divisors (see below), whose sum is σ = 71484. Its totient is φ = 19584.

The previous prime is 39989. The next prime is 40009.

It is a happy number.

40004 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 23104 + 16900 = 152^2 + 130^2 .

It is a junction number, because it is equal to n+sod(n) for n = 39973 and 40000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40009) by changing a digit.

40004 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 224 + ... + 360.

It is an arithmetic number, because the mean of its divisors is an integer number (5957).

2⁴⁰⁰⁰⁴ is an apocalyptic number.

It is an amenable number.

40004 is a deficient number, since it is larger than the sum of its proper divisors (31480).

40004 is a wasteful number, since it uses less digits than its factorization.

40004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 8.

The square root of 40004 is about 200.0099997500. The cubic root of 40004 is about 34.2006588795.

It can be divided in two parts, 4000 and 4, that added together give a palindrome (4004).

The spelling of 40004 in words is "forty thousand, four", and thus it is an eban number and an iban number.