355221 has 12 divisors (see below), whose sum is σ = 531180. Its totient is φ = 228480.

The previous prime is 355211. The next prime is 355261. The reversal of 355221 is 122553.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 119025 + 236196 = 345^2 + 486^2 .

It is not a de Polignac number, because 355221 - 2⁷ = 355093 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 355194 and 355203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (355211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 420 + ... + 941.

It is an arithmetic number, because the mean of its divisors is an integer number (44265).

2³⁵⁵²²¹ is an apocalyptic number.

It is an amenable number.

355221 is a deficient number, since it is larger than the sum of its proper divisors (175959).

355221 is a wasteful number, since it uses less digits than its factorization.

355221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1396 (or 1393 counting only the distinct ones).

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

The square root of 355221 is about 596.0041946161. The cubic root of 355221 is about 70.8216777439.

Adding to 355221 its reverse (122553), we get a palindrome (477774).

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

The spelling of 355221 in words is "three hundred fifty-five thousand, two hundred twenty-one".