221042045 has 16 divisors (see below), whose sum is σ = 307671168. Its totient is φ = 149307840.

The previous prime is 221042039. The next prime is 221042047. The reversal of 221042045 is 540240122.

It is a happy number.

It is not a de Polignac number, because 221042045 - 2⁶ = 221041981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221042047) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 44786 + ... + 49475.

It is an arithmetic number, because the mean of its divisors is an integer number (19229448).

Almost surely, 2^221042045 is an apocalyptic number.

It is an amenable number.

221042045 is a deficient number, since it is larger than the sum of its proper divisors (86629123).

221042045 is an equidigital number, since it uses as much as digits as its factorization.

221042045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94340.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 221042045 is about 14867.4828064471. The cubic root of 221042045 is about 604.6326983011.

Adding to 221042045 its reverse (540240122), we get a palindrome (761282167).

The spelling of 221042045 in words is "two hundred twenty-one million, forty-two thousand, forty-five".