51515421077 has 2 divisors, whose sum is σ = 51515421078. Its totient is φ = 51515421076.

The previous prime is 51515421073. The next prime is 51515421101. The reversal of 51515421077 is 77012451515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51470450641 + 44970436 = 226871^2 + 6706^2 .

It is a cyclic number.

It is not a de Polignac number, because 51515421077 - 2² = 51515421073 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51515421077.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51515421071) 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, 25757710538 + 25757710539.

It is an arithmetic number, because the mean of its divisors is an integer number (25757710539).

Almost surely, 2^51515421077 is an apocalyptic number.

It is an amenable number.

51515421077 is a deficient number, since it is larger than the sum of its proper divisors (1).

51515421077 is an equidigital number, since it uses as much as digits as its factorization.

51515421077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 49000, while the sum is 38.

The spelling of 51515421077 in words is "fifty-one billion, five hundred fifteen million, four hundred twenty-one thousand, seventy-seven".