43109221 has 2 divisors, whose sum is σ = 43109222. Its totient is φ = 43109220.

The previous prime is 43109219. The next prime is 43109243. The reversal of 43109221 is 12290134.

43109221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (43109243) can be obtained adding 43109221 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43046721 + 62500 = 6561^2 + 250^2 .

It is a cyclic number.

It is not a de Polignac number, because 43109221 - 2¹ = 43109219 is a prime.

Together with 43109219, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 43109192 and 43109201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43109281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21554610 + 21554611.

It is an arithmetic number, because the mean of its divisors is an integer number (21554611).

Almost surely, 2^43109221 is an apocalyptic number.

It is an amenable number.

43109221 is a deficient number, since it is larger than the sum of its proper divisors (1).

43109221 is an equidigital number, since it uses as much as digits as its factorization.

43109221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 43109221 is about 6565.7612658396. The cubic root of 43109221 is about 350.6361790003.

Adding to 43109221 its reverse (12290134), we get a palindrome (55399355).

It can be divided in two parts, 4310 and 9221, that added together give a palindrome (13531).

The spelling of 43109221 in words is "forty-three million, one hundred nine thousand, two hundred twenty-one".