100404 has 18 divisors (see below), whose sum is σ = 253890. Its totient is φ = 33456.

The previous prime is 100403. The next prime is 100411. The reversal of 100404 is 404001.

It can be written as a sum of positive squares in only one way, i.e., 90000 + 10404 = 300^2 + 102^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1359 + ... + 1430.

It is an arithmetic number, because the mean of its divisors is an integer number (14105).

2¹⁰⁰⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

100404 is an abundant number, since it is smaller than the sum of its proper divisors (153486).

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

100404 is a wasteful number, since it uses less digits than its factorization.

100404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2799 (or 2794 counting only the distinct ones).

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

The square root of 100404 is about 316.8659022363. The cubic root of 100404 is about 46.4783110784.

Adding to 100404 its reverse (404001), we get a palindrome (504405).

The spelling of 100404 in words is "one hundred thousand, four hundred four", and thus it is an iban number.