77961811 has 2 divisors, whose sum is σ = 77961812. Its totient is φ = 77961810.

The previous prime is 77961809. The next prime is 77961823. The reversal of 77961811 is 11816977.

It is a weak prime.

It is an emirp because it is prime and its reverse (11816977) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77961811 - 2¹ = 77961809 is a prime.

Together with 77961809, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (77961841) 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, 38980905 + 38980906.

It is an arithmetic number, because the mean of its divisors is an integer number (38980906).

Almost surely, 2^77961811 is an apocalyptic number.

77961811 is a deficient number, since it is larger than the sum of its proper divisors (1).

77961811 is an equidigital number, since it uses as much as digits as its factorization.

77961811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 40.

The square root of 77961811 is about 8829.5985752468. The cubic root of 77961811 is about 427.1961266318.

The spelling of 77961811 in words is "seventy-seven million, nine hundred sixty-one thousand, eight hundred eleven".