221210243 has 2 divisors, whose sum is σ = 221210244. Its totient is φ = 221210242.

The previous prime is 221210207. The next prime is 221210263. The reversal of 221210243 is 342012122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221210243 - 2⁸ = 221209987 is a prime.

It is not a weakly prime, because it can be changed into another prime (221210263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110605121 + 110605122.

It is an arithmetic number, because the mean of its divisors is an integer number (110605122).

Almost surely, 2^221210243 is an apocalyptic number.

221210243 is a deficient number, since it is larger than the sum of its proper divisors (1).

221210243 is an equidigital number, since it uses as much as digits as its factorization.

221210243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 221210243 is about 14873.1383036668. The cubic root of 221210243 is about 604.7860209059.

Adding to 221210243 its reverse (342012122), we get a palindrome (563222365).

The spelling of 221210243 in words is "two hundred twenty-one million, two hundred ten thousand, two hundred forty-three".