221355 has 12 divisors (see below), whose sum is σ = 383760. Its totient is φ = 118032.

The previous prime is 221327. The next prime is 221393. The reversal of 221355 is 553122.

It is a happy number.

221355 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221355 - 2⁷ = 221227 is a prime.

221355 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2415 + ... + 2504.

It is an arithmetic number, because the mean of its divisors is an integer number (31980).

2²²¹³⁵⁵ is an apocalyptic number.

221355 is a deficient number, since it is larger than the sum of its proper divisors (162405).

221355 is a wasteful number, since it uses less digits than its factorization.

221355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4930 (or 4927 counting only the distinct ones).

The product of its digits is 300, while the sum is 18.

The square root of 221355 is about 470.4837935572. The cubic root of 221355 is about 60.4917913413.

Adding to 221355 its reverse (553122), we get a palindrome (774477).

It can be divided in two parts, 221 and 355, that added together give a square (576 = 24²).

The spelling of 221355 in words is "two hundred twenty-one thousand, three hundred fifty-five".