221320243 has 2 divisors, whose sum is σ = 221320244. Its totient is φ = 221320242.

The previous prime is 221320223. The next prime is 221320271. The reversal of 221320243 is 342023122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221320243 - 2¹³ = 221312051 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221320243.

It is not a weakly prime, because it can be changed into another prime (221320213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110660121 + 110660122.

It is an arithmetic number, because the mean of its divisors is an integer number (110660122).

Almost surely, 2^221320243 is an apocalyptic number.

221320243 is a deficient number, since it is larger than the sum of its proper divisors (1).

221320243 is an equidigital number, since it uses as much as digits as its factorization.

221320243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 19.

The square root of 221320243 is about 14876.8357858787. The cubic root of 221320243 is about 604.8862504995.

Adding to 221320243 its reverse (342023122), we get a palindrome (563343365).

The spelling of 221320243 in words is "two hundred twenty-one million, three hundred twenty thousand, two hundred forty-three".