51147544561 has 2 divisors, whose sum is σ = 51147544562. Its totient is φ = 51147544560.

The previous prime is 51147544543. The next prime is 51147544573. The reversal of 51147544561 is 16544574115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46707854400 + 4439690161 = 216120^2 + 66631^2 .

It is a cyclic number.

It is not a de Polignac number, because 51147544561 - 2²³ = 51139155953 is a prime.

It is not a weakly prime, because it can be changed into another prime (51147544541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25573772280 + 25573772281.

It is an arithmetic number, because the mean of its divisors is an integer number (25573772281).

Almost surely, 2^51147544561 is an apocalyptic number.

It is an amenable number.

51147544561 is a deficient number, since it is larger than the sum of its proper divisors (1).

51147544561 is an equidigital number, since it uses as much as digits as its factorization.

51147544561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336000, while the sum is 43.

The spelling of 51147544561 in words is "fifty-one billion, one hundred forty-seven million, five hundred forty-four thousand, five hundred sixty-one".