51380087881 has 2 divisors, whose sum is σ = 51380087882. Its totient is φ = 51380087880.

The previous prime is 51380087879. The next prime is 51380087893. The reversal of 51380087881 is 18878008315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45183879225 + 6196208656 = 212565^2 + 78716^2 .

It is a cyclic number.

It is not a de Polignac number, because 51380087881 - 2¹ = 51380087879 is a prime.

It is a super-2 number, since 2×51380087881² (a number of 22 digits) contains 22 as substring.

Together with 51380087879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51380087081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25690043940 + 25690043941.

It is an arithmetic number, because the mean of its divisors is an integer number (25690043941).

Almost surely, 2^51380087881 is an apocalyptic number.

It is an amenable number.

51380087881 is a deficient number, since it is larger than the sum of its proper divisors (1).

51380087881 is an equidigital number, since it uses as much as digits as its factorization.

51380087881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 430080, while the sum is 49.

The spelling of 51380087881 in words is "fifty-one billion, three hundred eighty million, eighty-seven thousand, eight hundred eighty-one".