43243440221 has 4 divisors (see below), whose sum is σ = 43313527452. Its totient is φ = 43173352992.

The previous prime is 43243440211. The next prime is 43243440223. The reversal of 43243440221 is 12204434234.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17460715321 + 25782724900 = 132139^2 + 160570^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43243440221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43243440223) 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 in 3 ways as a sum of consecutive naturals, for example, 35042690 + ... + 35043923.

It is an arithmetic number, because the mean of its divisors is an integer number (10828381863).

Almost surely, 2^43243440221 is an apocalyptic number.

It is an amenable number.

43243440221 is a deficient number, since it is larger than the sum of its proper divisors (70087231).

43243440221 is an equidigital number, since it uses as much as digits as its factorization.

43243440221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70087230.

The product of its (nonzero) digits is 18432, while the sum is 29.

Adding to 43243440221 its reverse (12204434234), we get a palindrome (55447874455).

The spelling of 43243440221 in words is "forty-three billion, two hundred forty-three million, four hundred forty thousand, two hundred twenty-one".