1663960841 has 2 divisors, whose sum is σ = 1663960842. Its totient is φ = 1663960840.

The previous prime is 1663960819. The next prime is 1663960847. The reversal of 1663960841 is 1480693661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1646655241 + 17305600 = 40579^2 + 4160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1663960841 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1663960792 and 1663960801.

It is not a weakly prime, because it can be changed into another prime (1663960847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831980420 + 831980421.

It is an arithmetic number, because the mean of its divisors is an integer number (831980421).

Almost surely, 2^1663960841 is an apocalyptic number.

It is an amenable number.

1663960841 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663960841 is an equidigital number, since it uses as much as digits as its factorization.

1663960841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 44.

The square root of 1663960841 is about 40791.6761239349. The cubic root of 1663960841 is about 1184.9891317465.

The spelling of 1663960841 in words is "one billion, six hundred sixty-three million, nine hundred sixty thousand, eight hundred forty-one".