51815742805 has 8 divisors (see below), whose sum is σ = 63695449944. Its totient is φ = 40441555200.

The previous prime is 51815742767. The next prime is 51815742829. The reversal of 51815742805 is 50824751815.

51815742805 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 119990116 + 51695752689 = 10954^2 + 227367^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51815742805 - 2⁷ = 51815742677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126379656 + ... + 126380065.

It is an arithmetic number, because the mean of its divisors is an integer number (7961931243).

Almost surely, 2^51815742805 is an apocalyptic number.

It is an amenable number.

51815742805 is a deficient number, since it is larger than the sum of its proper divisors (11879707139).

51815742805 is a wasteful number, since it uses less digits than its factorization.

51815742805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252759767.

The product of its (nonzero) digits is 448000, while the sum is 46.

The spelling of 51815742805 in words is "fifty-one billion, eight hundred fifteen million, seven hundred forty-two thousand, eight hundred five".