1641368735509 has 2 divisors, whose sum is σ = 1641368735510. Its totient is φ = 1641368735508.

The previous prime is 1641368735387. The next prime is 1641368735519. The reversal of 1641368735509 is 9055378631461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1636007274225 + 5361461284 = 1279065^2 + 73222^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641368735509 - 2¹¹ = 1641368733461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641368735519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820684367754 + 820684367755.

It is an arithmetic number, because the mean of its divisors is an integer number (820684367755).

Almost surely, 2^{1641368735509} is an apocalyptic number.

It is an amenable number.

1641368735509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641368735509 is an equidigital number, since it uses as much as digits as its factorization.

1641368735509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16329600, while the sum is 58.

The spelling of 1641368735509 in words is "one trillion, six hundred forty-one billion, three hundred sixty-eight million, seven hundred thirty-five thousand, five hundred nine".