1404 has 24 divisors (see below), whose sum is σ = 3920. Its totient is φ = 432.

The previous prime is 1399. The next prime is 1409. The reversal of 1404 is 4041.

It is an interprime number because it is at equal distance from previous prime (1399) and next prime (1409).

It is a hoax number, since the sum of its digits (9) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an Ulam number.

It is a plaindrome in base 16.

It is a nialpdrome in base 12 and base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1409) by changing a digit.

1404 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 (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 102 + ... + 114.

1404 is the 24-th heptagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1960).

1404 is an abundant number, since it is smaller than the sum of its proper divisors (2516).

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

1404 is a wasteful number, since it uses less digits than its factorization.

1404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 1404 is about 37.4699879904. The cubic root of 1404 is about 11.1975334705.

Adding to 1404 its reverse (4041), we get a palindrome (5445).

It can be divided in two parts, 140 and 4, that added together give a square (144 = 12²).

The spelling of 1404 in words is "one thousand, four hundred four", and thus it is an iban number.