77823742169 has 2 divisors, whose sum is σ = 77823742170. Its totient is φ = 77823742168.

The previous prime is 77823742163. The next prime is 77823742181. The reversal of 77823742169 is 96124732877.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77778516544 + 45225625 = 278888^2 + 6725^2 .

It is an emirp because it is prime and its reverse (96124732877) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77823742169 - 2⁴ = 77823742153 is a prime.

It is a super-2 number, since 2×77823742169² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (77823742163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38911871084 + 38911871085.

It is an arithmetic number, because the mean of its divisors is an integer number (38911871085).

Almost surely, 2^77823742169 is an apocalyptic number.

It is an amenable number.

77823742169 is a deficient number, since it is larger than the sum of its proper divisors (1).

77823742169 is an equidigital number, since it uses as much as digits as its factorization.

77823742169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7112448, while the sum is 56.

The spelling of 77823742169 in words is "seventy-seven billion, eight hundred twenty-three million, seven hundred forty-two thousand, one hundred sixty-nine".