221357 has 8 divisors (see below), whose sum is σ = 243000. Its totient is φ = 200704.

The previous prime is 221327. The next prime is 221393. The reversal of 221357 is 753122.

221357 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 72361 + 148996 = 269^2 + 386^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221357 - 2⁸ = 221101 is a prime.

It is a Duffinian number.

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 221357.

It is not an unprimeable number, because it can be changed into a prime (221317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269 + ... + 717.

It is an arithmetic number, because the mean of its divisors is an integer number (30375).

2²²¹³⁵⁷ is an apocalyptic number.

It is an amenable number.

221357 is a deficient number, since it is larger than the sum of its proper divisors (21643).

221357 is a wasteful number, since it uses less digits than its factorization.

221357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495.

The product of its digits is 420, while the sum is 20.

The square root of 221357 is about 470.4859190242. The cubic root of 221357 is about 60.4919735271.

Adding to 221357 its reverse (753122), we get a palindrome (974479).

The spelling of 221357 in words is "two hundred twenty-one thousand, three hundred fifty-seven".