43930021 has 2 divisors, whose sum is σ = 43930022. Its totient is φ = 43930020.

The previous prime is 43929997. The next prime is 43930031. The reversal of 43930021 is 12003934.

43930021 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., 37039396 + 6890625 = 6086^2 + 2625^2 .

It is a cyclic number.

It is not a de Polignac number, because 43930021 - 2¹¹ = 43927973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 43929974 and 43930001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43930031) 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, 21965010 + 21965011.

It is an arithmetic number, because the mean of its divisors is an integer number (21965011).

Almost surely, 2^43930021 is an apocalyptic number.

It is an amenable number.

43930021 is a deficient number, since it is larger than the sum of its proper divisors (1).

43930021 is an equidigital number, since it uses as much as digits as its factorization.

43930021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 43930021 is about 6627.9726161172. The cubic root of 43930021 is about 352.8475749461.

Adding to 43930021 its reverse (12003934), we get a palindrome (55933955).

The spelling of 43930021 in words is "forty-three million, nine hundred thirty thousand, twenty-one".