77891113 has 2 divisors, whose sum is σ = 77891114. Its totient is φ = 77891112.

The previous prime is 77891111. The next prime is 77891123. The reversal of 77891113 is 31119877.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77580864 + 310249 = 8808^2 + 557^2 .

It is a cyclic number.

It is not a de Polignac number, because 77891113 - 2¹ = 77891111 is a prime.

Together with 77891111, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (77891111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38945556 + 38945557.

It is an arithmetic number, because the mean of its divisors is an integer number (38945557).

Almost surely, 2^77891113 is an apocalyptic number.

It is an amenable number.

77891113 is a deficient number, since it is larger than the sum of its proper divisors (1).

77891113 is an equidigital number, since it uses as much as digits as its factorization.

77891113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 37.

The square root of 77891113 is about 8825.5942009589. The cubic root of 77891113 is about 427.0669563569.

The spelling of 77891113 in words is "seventy-seven million, eight hundred ninety-one thousand, one hundred thirteen".