66044610520409 has 2 divisors, whose sum is σ = 66044610520410. Its totient is φ = 66044610520408.

The previous prime is 66044610520391. The next prime is 66044610520423. The reversal of 66044610520409 is 90402501644066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36493644754009 + 29550965766400 = 6040997^2 + 5436080^2 .

It is a cyclic number.

It is not a de Polignac number, because 66044610520409 - 2⁴⁰ = 64945098892633 is a prime.

It is a super-3 number, since 3×66044610520409³ (a number of 42 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (66044612520409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33022305260204 + 33022305260205.

It is an arithmetic number, because the mean of its divisors is an integer number (33022305260205).

Almost surely, 2^{66044610520409} is an apocalyptic number.

It is an amenable number.

66044610520409 is a deficient number, since it is larger than the sum of its proper divisors (1).

66044610520409 is an equidigital number, since it uses as much as digits as its factorization.

66044610520409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1244160, while the sum is 47.

The spelling of 66044610520409 in words is "sixty-six trillion, forty-four billion, six hundred ten million, five hundred twenty thousand, four hundred nine".