51900635666881 has 2 divisors, whose sum is σ = 51900635666882. Its totient is φ = 51900635666880.

The previous prime is 51900635666857. The next prime is 51900635666909. The reversal of 51900635666881 is 18866653600915.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38703516076225 + 13197119590656 = 6221215^2 + 3632784^2 .

It is a cyclic number.

It is not a de Polignac number, because 51900635666881 - 2¹⁹ = 51900635142593 is a prime.

It is a super-2 number, since 2×51900635666881² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51900635666821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25950317833440 + 25950317833441.

It is an arithmetic number, because the mean of its divisors is an integer number (25950317833441).

Almost surely, 2^{51900635666881} is an apocalyptic number.

It is an amenable number.

51900635666881 is a deficient number, since it is larger than the sum of its proper divisors (1).

51900635666881 is an equidigital number, since it uses as much as digits as its factorization.

51900635666881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 55987200, while the sum is 64.

The spelling of 51900635666881 in words is "fifty-one trillion, nine hundred billion, six hundred thirty-five million, six hundred sixty-six thousand, eight hundred eighty-one".