51651110066561 has 2 divisors, whose sum is σ = 51651110066562. Its totient is φ = 51651110066560.

The previous prime is 51651110066513. The next prime is 51651110066603. The reversal of 51651110066561 is 16566001115615.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32667443215936 + 18983666850625 = 5715544^2 + 4357025^2 .

It is a cyclic number.

It is not a de Polignac number, because 51651110066561 - 2⁶ = 51651110066497 is a prime.

It is a super-2 number, since 2×51651110066561² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51651110068561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25825555033280 + 25825555033281.

It is an arithmetic number, because the mean of its divisors is an integer number (25825555033281).

Almost surely, 2^{51651110066561} is an apocalyptic number.

It is an amenable number.

51651110066561 is a deficient number, since it is larger than the sum of its proper divisors (1).

51651110066561 is an equidigital number, since it uses as much as digits as its factorization.

51651110066561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162000, while the sum is 44.

The spelling of 51651110066561 in words is "fifty-one trillion, six hundred fifty-one billion, one hundred ten million, sixty-six thousand, five hundred sixty-one".