43220021221 has 16 divisors (see below), whose sum is σ = 49007472640. Its totient is φ = 37785528000.

The previous prime is 43220021167. The next prime is 43220021233. The reversal of 43220021221 is 12212002234.

It is a de Polignac number, because none of the positive numbers 2^k-43220021221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43220021261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 989596 + ... + 1032346.

It is an arithmetic number, because the mean of its divisors is an integer number (3062967040).

Almost surely, 2^43220021221 is an apocalyptic number.

It is an amenable number.

43220021221 is a deficient number, since it is larger than the sum of its proper divisors (5787451419).

43220021221 is a wasteful number, since it uses less digits than its factorization.

43220021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46876.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 43220021221 its reverse (12212002234), we get a palindrome (55432023455).

The spelling of 43220021221 in words is "forty-three billion, two hundred twenty million, twenty-one thousand, two hundred twenty-one".