43440243221 has 4 divisors (see below), whose sum is σ = 45328949472. Its totient is φ = 41551536972.

The previous prime is 43440243173. The next prime is 43440243227. The reversal of 43440243221 is 12234204434.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-43440243221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43440243227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 944353091 + ... + 944353136.

It is an arithmetic number, because the mean of its divisors is an integer number (11332237368).

Almost surely, 2^43440243221 is an apocalyptic number.

It is an amenable number.

43440243221 is a deficient number, since it is larger than the sum of its proper divisors (1888706251).

43440243221 is a wasteful number, since it uses less digits than its factorization.

43440243221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1888706250.

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

Adding to 43440243221 its reverse (12234204434), we get a palindrome (55674447655).

The spelling of 43440243221 in words is "forty-three billion, four hundred forty million, two hundred forty-three thousand, two hundred twenty-one".