500056561661 has 2 divisors, whose sum is σ = 500056561662. Its totient is φ = 500056561660.

The previous prime is 500056561643. The next prime is 500056561663. The reversal of 500056561661 is 166165650005.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 287102000761 + 212954560900 = 535819^2 + 461470^2 .

It is a cyclic number.

It is not a de Polignac number, because 500056561661 - 2⁶ = 500056561597 is a prime.

It is a Sophie Germain prime.

Together with 500056561663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (500056561663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250028280830 + 250028280831.

It is an arithmetic number, because the mean of its divisors is an integer number (250028280831).

Almost surely, 2^500056561661 is an apocalyptic number.

It is an amenable number.

500056561661 is a deficient number, since it is larger than the sum of its proper divisors (1).

500056561661 is an equidigital number, since it uses as much as digits as its factorization.

500056561661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162000, while the sum is 41.

The spelling of 500056561661 in words is "five hundred billion, fifty-six million, five hundred sixty-one thousand, six hundred sixty-one".