221242105 has 12 divisors (see below), whose sum is σ = 308836260. Its totient is φ = 151708704.

The previous prime is 221242103. The next prime is 221242127. The reversal of 221242105 is 501242122.

It can be written as a sum of positive squares in 2 ways, for example, as 172633321 + 48608784 = 13139^2 + 6972^2 .

It is not a de Polignac number, because 221242105 - 2¹ = 221242103 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221242103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 451270 + ... + 451759.

It is an arithmetic number, because the mean of its divisors is an integer number (25736355).

Almost surely, 2^221242105 is an apocalyptic number.

It is an amenable number.

221242105 is a deficient number, since it is larger than the sum of its proper divisors (87594155).

221242105 is an equidigital number, since it uses as much as digits as its factorization.

221242105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 903048 (or 903041 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 221242105 is about 14874.2093907542. The cubic root of 221242105 is about 604.8150562810.

Adding to 221242105 its reverse (501242122), we get a palindrome (722484227).

The spelling of 221242105 in words is "two hundred twenty-one million, two hundred forty-two thousand, one hundred five".