221404 has 6 divisors (see below), whose sum is σ = 387464. Its totient is φ = 110700.

The previous prime is 221401. The next prime is 221411. The reversal of 221404 is 404122.

221404 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27672 + ... + 27679.

2²²¹⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

221404 is a deficient number, since it is larger than the sum of its proper divisors (166060).

221404 is a wasteful number, since it uses less digits than its factorization.

221404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55355 (or 55353 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 221404 is about 470.5358647330. The cubic root of 221404 is about 60.4962545777.

Adding to 221404 its reverse (404122), we get a palindrome (625526).

It can be divided in two parts, 221 and 404, that added together give a 4-th power (625 = 5⁴).

The spelling of 221404 in words is "two hundred twenty-one thousand, four hundred four", and thus it is an iban number.