77575909 has 2 divisors, whose sum is σ = 77575910. Its totient is φ = 77575908.

The previous prime is 77575903. The next prime is 77575931. The reversal of 77575909 is 90957577.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66830625 + 10745284 = 8175^2 + 3278^2 .

It is an emirp because it is prime and its reverse (90957577) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77575909 - 2¹¹ = 77573861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77575903) 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, 38787954 + 38787955.

It is an arithmetic number, because the mean of its divisors is an integer number (38787955).

Almost surely, 2^77575909 is an apocalyptic number.

It is an amenable number.

77575909 is a deficient number, since it is larger than the sum of its proper divisors (1).

77575909 is an equidigital number, since it uses as much as digits as its factorization.

77575909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 694575, while the sum is 49.

The square root of 77575909 is about 8807.7187171253. The cubic root of 77575909 is about 426.4901032004.

The spelling of 77575909 in words is "seventy-seven million, five hundred seventy-five thousand, nine hundred nine".