3904 has 14 divisors (see below), whose sum is σ = 7874. Its totient is φ = 1920.

The previous prime is 3889. The next prime is 3907. The reversal of 3904 is 4093.

3904 is nontrivially palindromic in base 3.

It can be written as a sum of positive squares in only one way, i.e., 2304 + 1600 = 48^2 + 40^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

3904 is an undulating number in base 11.

It is a plaindrome in base 14.

It is a nialpdrome in base 4, base 8 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3907) by changing a digit.

3904 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34 + ... + 94.

2³⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3937).

3904 is an abundant number, since it is smaller than the sum of its proper divisors (3970).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3904 is an equidigital number, since it uses as much as digits as its factorization.

3904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 3904 is about 62.4819974073. The cubic root of 3904 is about 15.7459887324.

Adding to 3904 its reverse (4093), we get a palindrome (7997).

The spelling of 3904 in words is "three thousand, nine hundred four".