221331355 has 8 divisors (see below), whose sum is σ = 303540192. Its totient is φ = 151770048.

The previous prime is 221331349. The next prime is 221331379. The reversal of 221331355 is 553133122.

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 221331355 - 2⁹ = 221330843 is a prime.

It is a super-2 number, since 2×221331355² = 97975137412272050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3161842 + ... + 3161911.

It is an arithmetic number, because the mean of its divisors is an integer number (37942524).

Almost surely, 2^221331355 is an apocalyptic number.

221331355 is a deficient number, since it is larger than the sum of its proper divisors (82208837).

221331355 is an equidigital number, since it uses as much as digits as its factorization.

221331355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6323765.

The product of its digits is 2700, while the sum is 25.

The square root of 221331355 is about 14877.2092477050. The cubic root of 221331355 is about 604.8963736638.

Adding to 221331355 its reverse (553133122), we get a palindrome (774464477).

The spelling of 221331355 in words is "two hundred twenty-one million, three hundred thirty-one thousand, three hundred fifty-five".