181404 has 18 divisors (see below), whose sum is σ = 458640. Its totient is φ = 60456.

The previous prime is 181399. The next prime is 181409. The reversal of 181404 is 404181.

It is an interprime number because it is at equal distance from previous prime (181399) and next prime (181409).

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

It is a super-2 number, since 2×181404² = 65814822432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 181404.

It is not an unprimeable number, because it can be changed into a prime (181409) 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, 2484 + ... + 2555.

It is an arithmetic number, because the mean of its divisors is an integer number (25480).

2¹⁸¹⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

181404 is an abundant number, since it is smaller than the sum of its proper divisors (277236).

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

181404 is a wasteful number, since it uses less digits than its factorization.

181404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5049 (or 5044 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 181404 is about 425.9154845741. The cubic root of 181404 is about 56.6085833146.

Adding to 181404 its reverse (404181), we get a palindrome (585585).

It can be divided in two parts, 181 and 404, that added together give a palindrome (585).

The spelling of 181404 in words is "one hundred eighty-one thousand, four hundred four".