77724488161 has 2 divisors, whose sum is σ = 77724488162. Its totient is φ = 77724488160.

The previous prime is 77724488137. The next prime is 77724488167. The reversal of 77724488161 is 16188442777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77704907536 + 19580625 = 278756^2 + 4425^2 .

It is a cyclic number.

It is not a de Polignac number, because 77724488161 - 2²¹ = 77722391009 is a prime.

It is not a weakly prime, because it can be changed into another prime (77724488167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38862244080 + 38862244081.

It is an arithmetic number, because the mean of its divisors is an integer number (38862244081).

Almost surely, 2^77724488161 is an apocalyptic number.

It is an amenable number.

77724488161 is a deficient number, since it is larger than the sum of its proper divisors (1).

77724488161 is an equidigital number, since it uses as much as digits as its factorization.

77724488161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4214784, while the sum is 55.

The spelling of 77724488161 in words is "seventy-seven billion, seven hundred twenty-four million, four hundred eighty-eight thousand, one hundred sixty-one".