77663491 has 2 divisors, whose sum is σ = 77663492. Its totient is φ = 77663490.

The previous prime is 77663483. The next prime is 77663503. The reversal of 77663491 is 19436677.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77663491 - 2³ = 77663483 is a prime.

It is not a weakly prime, because it can be changed into another prime (77663441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38831745 + 38831746.

It is an arithmetic number, because the mean of its divisors is an integer number (38831746).

Almost surely, 2^77663491 is an apocalyptic number.

77663491 is a deficient number, since it is larger than the sum of its proper divisors (1).

77663491 is an equidigital number, since it uses as much as digits as its factorization.

77663491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 43.

The square root of 77663491 is about 8812.6892036427. The cubic root of 77663491 is about 426.6505430783.

The spelling of 77663491 in words is "seventy-seven million, six hundred sixty-three thousand, four hundred ninety-one".