51520549477 has 2 divisors, whose sum is σ = 51520549478. Its totient is φ = 51520549476.

The previous prime is 51520549463. The next prime is 51520549481. The reversal of 51520549477 is 77494502515.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44321196676 + 7199352801 = 210526^2 + 84849^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51520549477 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51520549477.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51520349477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25760274738 + 25760274739.

It is an arithmetic number, because the mean of its divisors is an integer number (25760274739).

Almost surely, 2^51520549477 is an apocalyptic number.

It is an amenable number.

51520549477 is a deficient number, since it is larger than the sum of its proper divisors (1).

51520549477 is an equidigital number, since it uses as much as digits as its factorization.

51520549477 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764000, while the sum is 49.

The spelling of 51520549477 in words is "fifty-one billion, five hundred twenty million, five hundred forty-nine thousand, four hundred seventy-seven".