50681728661 has 4 divisors (see below), whose sum is σ = 50687567532. Its totient is φ = 50675889792.

The previous prime is 50681728639. The next prime is 50681728673. The reversal of 50681728661 is 16682718605.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27670659025 + 23011069636 = 166345^2 + 151694^2 .

It is a cyclic number.

It is not a de Polignac number, because 50681728661 - 2¹⁰ = 50681727637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (50681728681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2906396 + ... + 2923781.

It is an arithmetic number, because the mean of its divisors is an integer number (12671891883).

Almost surely, 2^50681728661 is an apocalyptic number.

It is an amenable number.

50681728661 is a deficient number, since it is larger than the sum of its proper divisors (5838871).

50681728661 is an equidigital number, since it uses as much as digits as its factorization.

50681728661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5838870.

The product of its (nonzero) digits is 967680, while the sum is 50.

The spelling of 50681728661 in words is "fifty billion, six hundred eighty-one million, seven hundred twenty-eight thousand, six hundred sixty-one".