77820563 has 2 divisors, whose sum is σ = 77820564. Its totient is φ = 77820562.

The previous prime is 77820559. The next prime is 77820581. The reversal of 77820563 is 36502877.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77820563 - 2² = 77820559 is a prime.

It is a super-3 number, since 3×77820563³ (a number of 25 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (77820553) 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, 38910281 + 38910282.

It is an arithmetic number, because the mean of its divisors is an integer number (38910282).

Almost surely, 2^77820563 is an apocalyptic number.

77820563 is a deficient number, since it is larger than the sum of its proper divisors (1).

77820563 is an equidigital number, since it uses as much as digits as its factorization.

77820563 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 77820563 is about 8821.5963974782. The cubic root of 77820563 is about 426.9379785492.

The spelling of 77820563 in words is "seventy-seven million, eight hundred twenty thousand, five hundred sixty-three".