1663772773661 has 2 divisors, whose sum is σ = 1663772773662. Its totient is φ = 1663772773660.

The previous prime is 1663772773643. The next prime is 1663772773669.

1663772773661 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., 1023524749636 + 640248024025 = 1011694^2 + 800155^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 1663772773661 - 2¹⁰ = 1663772772637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1663772773594 and 1663772773603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1663772773669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831886386830 + 831886386831.

It is an arithmetic number, because the mean of its divisors is an integer number (831886386831).

Almost surely, 2^{1663772773661} is an apocalyptic number.

It is an amenable number.

1663772773661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663772773661 is an equidigital number, since it uses as much as digits as its factorization.

1663772773661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56010528, while the sum is 62.

The spelling of 1663772773661 in words is "one trillion, six hundred sixty-three billion, seven hundred seventy-two million, seven hundred seventy-three thousand, six hundred sixty-one".