51355010981 has 2 divisors, whose sum is σ = 51355010982. Its totient is φ = 51355010980.

The previous prime is 51355010939. The next prime is 51355011011. The reversal of 51355010981 is 18901055315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50370620356 + 984390625 = 224434^2 + 31375^2 .

It is a cyclic number.

It is not a de Polignac number, because 51355010981 - 2¹⁴ = 51354994597 is a prime.

It is a super-2 number, since 2×51355010981² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51355010281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25677505490 + 25677505491.

It is an arithmetic number, because the mean of its divisors is an integer number (25677505491).

Almost surely, 2^51355010981 is an apocalyptic number.

It is an amenable number.

51355010981 is a deficient number, since it is larger than the sum of its proper divisors (1).

51355010981 is an equidigital number, since it uses as much as digits as its factorization.

51355010981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27000, while the sum is 38.

The spelling of 51355010981 in words is "fifty-one billion, three hundred fifty-five million, ten thousand, nine hundred eighty-one".