7904 has 24 divisors (see below), whose sum is σ = 17640. Its totient is φ = 3456.

The previous prime is 7901. The next prime is 7907. The reversal of 7904 is 4097.

It is an interprime number because it is at equal distance from previous prime (7901) and next prime (7907).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7901) 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, 407 + ... + 425.

It is an arithmetic number, because the mean of its divisors is an integer number (735).

2⁷⁹⁰⁴ 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 7904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8820).

7904 is an abundant number, since it is smaller than the sum of its proper divisors (9736).

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

7904 is a wasteful number, since it uses less digits than its factorization.

7904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 7904 is about 88.9044430836. The cubic root of 7904 is about 19.9196778494.

It can be divided in two parts, 790 and 4, that multiplied together give a triangular number (3160 = T₇₉).

The spelling of 7904 in words is "seven thousand, nine hundred four".