221844289 has 2 divisors, whose sum is σ = 221844290. Its totient is φ = 221844288.

The previous prime is 221844283. The next prime is 221844313. The reversal of 221844289 is 982448122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 129049600 + 92794689 = 11360^2 + 9633^2 .

It is a cyclic number.

It is not a de Polignac number, because 221844289 - 2³ = 221844281 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (221844281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110922144 + 110922145.

It is an arithmetic number, because the mean of its divisors is an integer number (110922145).

Almost surely, 2^221844289 is an apocalyptic number.

It is an amenable number.

221844289 is a deficient number, since it is larger than the sum of its proper divisors (1).

221844289 is an equidigital number, since it uses as much as digits as its factorization.

221844289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 73728, while the sum is 40.

The square root of 221844289 is about 14894.4381901433. The cubic root of 221844289 is about 605.3632943135.

The spelling of 221844289 in words is "two hundred twenty-one million, eight hundred forty-four thousand, two hundred eighty-nine".