51020521217 has 2 divisors, whose sum is σ = 51020521218. Its totient is φ = 51020521216.

The previous prime is 51020521133. The next prime is 51020521241. The reversal of 51020521217 is 71212502015.

51020521217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31872603841 + 19147917376 = 178529^2 + 138376^2 .

It is a cyclic number.

It is not a de Polignac number, because 51020521217 - 2¹⁰ = 51020520193 is a prime.

It is a super-2 number, since 2×51020521217² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51020521117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25510260608 + 25510260609.

It is an arithmetic number, because the mean of its divisors is an integer number (25510260609).

Almost surely, 2^51020521217 is an apocalyptic number.

It is an amenable number.

51020521217 is a deficient number, since it is larger than the sum of its proper divisors (1).

51020521217 is an equidigital number, since it uses as much as digits as its factorization.

51020521217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1400, while the sum is 26.

The spelling of 51020521217 in words is "fifty-one billion, twenty million, five hundred twenty-one thousand, two hundred seventeen".