51210534581 has 2 divisors, whose sum is σ = 51210534582. Its totient is φ = 51210534580.

The previous prime is 51210534521. The next prime is 51210534607. The reversal of 51210534581 is 18543501215.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43407639025 + 7802895556 = 208345^2 + 88334^2 .

It is a cyclic number.

It is not a de Polignac number, because 51210534581 - 2²⁶ = 51143425717 is a prime.

It is a super-2 number, since 2×51210534581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51210534521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25605267290 + 25605267291.

It is an arithmetic number, because the mean of its divisors is an integer number (25605267291).

Almost surely, 2^51210534581 is an apocalyptic number.

It is an amenable number.

51210534581 is a deficient number, since it is larger than the sum of its proper divisors (1).

51210534581 is an equidigital number, since it uses as much as digits as its factorization.

51210534581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24000, while the sum is 35.

The spelling of 51210534581 in words is "fifty-one billion, two hundred ten million, five hundred thirty-four thousand, five hundred eighty-one".