221324261 has 2 divisors, whose sum is σ = 221324262. Its totient is φ = 221324260.

The previous prime is 221324227. The next prime is 221324291. The reversal of 221324261 is 162423122.

It is a happy number.

221324261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173976100 + 47348161 = 13190^2 + 6881^2 .

It is a cyclic number.

It is not a de Polignac number, because 221324261 - 2¹⁰ = 221323237 is a prime.

It is a super-2 number, since 2×221324261² = 97968857014392242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221324291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110662130 + 110662131.

It is an arithmetic number, because the mean of its divisors is an integer number (110662131).

Almost surely, 2^221324261 is an apocalyptic number.

It is an amenable number.

221324261 is a deficient number, since it is larger than the sum of its proper divisors (1).

221324261 is an equidigital number, since it uses as much as digits as its factorization.

221324261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 23.

The square root of 221324261 is about 14876.9708274232. The cubic root of 221324261 is about 604.8899109845.

Adding to 221324261 its reverse (162423122), we get a palindrome (383747383).

The spelling of 221324261 in words is "two hundred twenty-one million, three hundred twenty-four thousand, two hundred sixty-one".