51435025561 has 2 divisors, whose sum is σ = 51435025562. Its totient is φ = 51435025560.

The previous prime is 51435025513. The next prime is 51435025589. The reversal of 51435025561 is 16552053415.

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., 51356171161 + 78854400 = 226619^2 + 8880^2 .

It is a cyclic number.

It is not a de Polignac number, because 51435025561 - 2¹⁹ = 51434501273 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51435025561.

It is not a weakly prime, because it can be changed into another prime (51435025361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25717512780 + 25717512781.

It is an arithmetic number, because the mean of its divisors is an integer number (25717512781).

Almost surely, 2^51435025561 is an apocalyptic number.

It is an amenable number.

51435025561 is a deficient number, since it is larger than the sum of its proper divisors (1).

51435025561 is an equidigital number, since it uses as much as digits as its factorization.

51435025561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90000, while the sum is 37.

Adding to 51435025561 its reverse (16552053415), we get a palindrome (67987078976).

The spelling of 51435025561 in words is "fifty-one billion, four hundred thirty-five million, twenty-five thousand, five hundred sixty-one".