77344615891 has 2 divisors, whose sum is σ = 77344615892. Its totient is φ = 77344615890.

The previous prime is 77344615861. The next prime is 77344615937. The reversal of 77344615891 is 19851644377.

It is a weak prime.

It is an emirp because it is prime and its reverse (19851644377) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77344615891 - 2³³ = 68754681299 is a prime.

It is not a weakly prime, because it can be changed into another prime (77344615801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38672307945 + 38672307946.

It is an arithmetic number, because the mean of its divisors is an integer number (38672307946).

Almost surely, 2^77344615891 is an apocalyptic number.

77344615891 is a deficient number, since it is larger than the sum of its proper divisors (1).

77344615891 is an equidigital number, since it uses as much as digits as its factorization.

77344615891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5080320, while the sum is 55.

The spelling of 77344615891 in words is "seventy-seven billion, three hundred forty-four million, six hundred fifteen thousand, eight hundred ninety-one".