221321266 has 8 divisors (see below), whose sum is σ = 351510300. Its totient is φ = 104151168.

The previous prime is 221321251. The next prime is 221321267. The reversal of 221321266 is 662123122.

221321266 is digitally balanced in base 3, 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 2 ways, for example, as 218005225 + 3316041 = 14765^2 + 1821^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 221321266.

It is not an unprimeable number, because it can be changed into a prime (221321267) 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 3 ways as a sum of consecutive naturals, for example, 3254691 + ... + 3254758.

Almost surely, 2^221321266 is an apocalyptic number.

221321266 is a deficient number, since it is larger than the sum of its proper divisors (130189034).

221321266 is a wasteful number, since it uses less digits than its factorization.

221321266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6509468.

The product of its digits is 1728, while the sum is 25.

The square root of 221321266 is about 14876.8701681503. The cubic root of 221321266 is about 604.8871824789.

Adding to 221321266 its reverse (662123122), we get a palindrome (883444388).

The spelling of 221321266 in words is "two hundred twenty-one million, three hundred twenty-one thousand, two hundred sixty-six".