43668603521 has 2 divisors, whose sum is σ = 43668603522. Its totient is φ = 43668603520.

The previous prime is 43668603497. The next prime is 43668603527. The reversal of 43668603521 is 12530686634.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43320594496 + 348009025 = 208136^2 + 18655^2 .

It is a cyclic number.

It is not a de Polignac number, because 43668603521 - 2⁶ = 43668603457 is a prime.

It is not a weakly prime, because it can be changed into another prime (43668603527) 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, 21834301760 + 21834301761.

It is an arithmetic number, because the mean of its divisors is an integer number (21834301761).

Almost surely, 2^43668603521 is an apocalyptic number.

It is an amenable number.

43668603521 is a deficient number, since it is larger than the sum of its proper divisors (1).

43668603521 is an equidigital number, since it uses as much as digits as its factorization.

43668603521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 43668603521 in words is "forty-three billion, six hundred sixty-eight million, six hundred three thousand, five hundred twenty-one".