221244345 has 32 divisors (see below), whose sum is σ = 449514240. Its totient is φ = 101139840.

The previous prime is 221244329. The next prime is 221244347. The reversal of 221244345 is 543442122.

221244345 is a `hidden beast` number, since 2 + 212 + 443 + 4 + 5 = 666.

It is not a de Polignac number, because 221244345 - 2⁴ = 221244329 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (221244347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 116116 + ... + 118005.

It is an arithmetic number, because the mean of its divisors is an integer number (14047320).

Almost surely, 2^221244345 is an apocalyptic number.

It is an amenable number.

221244345 is an abundant number, since it is smaller than the sum of its proper divisors (228269895).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221244345 is a wasteful number, since it uses less digits than its factorization.

221244345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234142 (or 234136 counting only the distinct ones).

The product of its digits is 7680, while the sum is 27.

The square root of 221244345 is about 14874.2846886834. The cubic root of 221244345 is about 604.8170974554.

Adding to 221244345 its reverse (543442122), we get a palindrome (764686467).

The spelling of 221244345 in words is "two hundred twenty-one million, two hundred forty-four thousand, three hundred forty-five".