51726805961 has 4 divisors (see below), whose sum is σ = 51728769924. Its totient is φ = 51724842000.

The previous prime is 51726805919. The next prime is 51726806009. The reversal of 51726805961 is 16950862715.

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 3615015625 + 48111790336 = 60125^2 + 219344^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51726805961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51726805261) 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, 941930 + ... + 995331.

It is an arithmetic number, because the mean of its divisors is an integer number (12932192481).

Almost surely, 2^51726805961 is an apocalyptic number.

It is an amenable number.

51726805961 is a deficient number, since it is larger than the sum of its proper divisors (1963963).

51726805961 is a wasteful number, since it uses less digits than its factorization.

51726805961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1963962.

The product of its (nonzero) digits is 907200, while the sum is 50.

The spelling of 51726805961 in words is "fifty-one billion, seven hundred twenty-six million, eight hundred five thousand, nine hundred sixty-one".