51806312101 has 4 divisors (see below), whose sum is σ = 51876989932. Its totient is φ = 51735634272.

The previous prime is 51806312081. The next prime is 51806312143. The reversal of 51806312101 is 10121360815.

It is a Cunningham number, because it is equal to 227610²+1.

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 50681715876 + 1124596225 = 225126^2 + 33535^2 .

It is a cyclic number.

It is not a de Polignac number, because 51806312101 - 2⁵ = 51806312069 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51806312101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51806312161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35337816 + ... + 35339281.

It is an arithmetic number, because the mean of its divisors is an integer number (12969247483).

Almost surely, 2^51806312101 is an apocalyptic number.

It is an amenable number.

51806312101 is a deficient number, since it is larger than the sum of its proper divisors (70677831).

51806312101 is an equidigital number, since it uses as much as digits as its factorization.

51806312101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70677830.

The product of its (nonzero) digits is 1440, while the sum is 28.

Adding to 51806312101 its reverse (10121360815), we get a palindrome (61927672916).

The spelling of 51806312101 in words is "fifty-one billion, eight hundred six million, three hundred twelve thousand, one hundred one".