51110317681 has 2 divisors, whose sum is σ = 51110317682. Its totient is φ = 51110317680.

The previous prime is 51110317639. The next prime is 51110317703. The reversal of 51110317681 is 18671301115.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33319026225 + 17791291456 = 182535^2 + 133384^2 .

It is a cyclic number.

It is not a de Polignac number, because 51110317681 - 2⁷ = 51110317553 is a prime.

It is a super-2 number, since 2×51110317681² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51110317631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25555158840 + 25555158841.

It is an arithmetic number, because the mean of its divisors is an integer number (25555158841).

Almost surely, 2^51110317681 is an apocalyptic number.

It is an amenable number.

51110317681 is a deficient number, since it is larger than the sum of its proper divisors (1).

51110317681 is an equidigital number, since it uses as much as digits as its factorization.

51110317681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 34.

Adding to 51110317681 its reverse (18671301115), we get a palindrome (69781618796).

The spelling of 51110317681 in words is "fifty-one billion, one hundred ten million, three hundred seventeen thousand, six hundred eighty-one".