1641723281797 has 2 divisors, whose sum is σ = 1641723281798. Its totient is φ = 1641723281796.

The previous prime is 1641723281789. The next prime is 1641723281837. The reversal of 1641723281797 is 7971823271461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1221889262881 + 419834018916 = 1105391^2 + 647946^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641723281797 - 2³ = 1641723281789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641723281897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820861640898 + 820861640899.

It is an arithmetic number, because the mean of its divisors is an integer number (820861640899).

Almost surely, 2^{1641723281797} is an apocalyptic number.

It is an amenable number.

1641723281797 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641723281797 is an equidigital number, since it uses as much as digits as its factorization.

1641723281797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7112448, while the sum is 58.

The spelling of 1641723281797 in words is "one trillion, six hundred forty-one billion, seven hundred twenty-three million, two hundred eighty-one thousand, seven hundred ninety-seven".