1643446443461 has 2 divisors, whose sum is σ = 1643446443462. Its totient is φ = 1643446443460.

The previous prime is 1643446443437. The next prime is 1643446443473.

1643446443461 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1612978740961 + 30467702500 = 1270031^2 + 174550^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 1643446443461 - 2¹⁰ = 1643446442437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1643446443491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821723221730 + 821723221731.

It is an arithmetic number, because the mean of its divisors is an integer number (821723221731).

Almost surely, 2^{1643446443461} is an apocalyptic number.

It is an amenable number.

1643446443461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1643446443461 is an equidigital number, since it uses as much as digits as its factorization.

1643446443461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7962624, while the sum is 50.

The spelling of 1643446443461 in words is "one trillion, six hundred forty-three billion, four hundred forty-six million, four hundred forty-three thousand, four hundred sixty-one".