77793913 has 2 divisors, whose sum is σ = 77793914. Its totient is φ = 77793912.

The previous prime is 77793899. The next prime is 77793929. The reversal of 77793913 is 31939777.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72812089 + 4981824 = 8533^2 + 2232^2 .

It is an emirp because it is prime and its reverse (31939777) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77793913 is a prime.

It is not a weakly prime, because it can be changed into another prime (77793953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38896956 + 38896957.

It is an arithmetic number, because the mean of its divisors is an integer number (38896957).

Almost surely, 2^77793913 is an apocalyptic number.

It is an amenable number.

77793913 is a deficient number, since it is larger than the sum of its proper divisors (1).

77793913 is an equidigital number, since it uses as much as digits as its factorization.

77793913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 250047, while the sum is 46.

The square root of 77793913 is about 8820.0857705580. The cubic root of 77793913 is about 426.8892373778.

The spelling of 77793913 in words is "seventy-seven million, seven hundred ninety-three thousand, nine hundred thirteen".