77688469 has 2 divisors, whose sum is σ = 77688470. Its totient is φ = 77688468.

The previous prime is 77688433. The next prime is 77688497. The reversal of 77688469 is 96488677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44395569 + 33292900 = 6663^2 + 5770^2 .

It is a cyclic number.

It is not a de Polignac number, because 77688469 - 2⁷ = 77688341 is a prime.

It is a super-2 number, since 2×77688469² = 12070996431127922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77688409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38844234 + 38844235.

It is an arithmetic number, because the mean of its divisors is an integer number (38844235).

Almost surely, 2^77688469 is an apocalyptic number.

It is an amenable number.

77688469 is a deficient number, since it is larger than the sum of its proper divisors (1).

77688469 is an equidigital number, since it uses as much as digits as its factorization.

77688469 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4064256, while the sum is 55.

The square root of 77688469 is about 8814.1062507778. The cubic root of 77688469 is about 426.6962777165.

The spelling of 77688469 in words is "seventy-seven million, six hundred eighty-eight thousand, four hundred sixty-nine".