9994788457 has 2 divisors, whose sum is σ = 9994788458. Its totient is φ = 9994788456.

The previous prime is 9994788403. The next prime is 9994788487. The reversal of 9994788457 is 7548874999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9714862096 + 279926361 = 98564^2 + 16731^2 .

It is an emirp because it is prime and its reverse (7548874999) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9994788457 is a prime.

It is not a weakly prime, because it can be changed into another prime (9994788487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4997394228 + 4997394229.

It is an arithmetic number, because the mean of its divisors is an integer number (4997394229).

Almost surely, 2^9994788457 is an apocalyptic number.

It is an amenable number.

9994788457 is a deficient number, since it is larger than the sum of its proper divisors (1).

9994788457 is an equidigital number, since it uses as much as digits as its factorization.

9994788457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 182891520, while the sum is 70.

The square root of 9994788457 is about 99973.9388890925. The cubic root of 9994788457 is about 2154.0603606956.

The spelling of 9994788457 in words is "nine billion, nine hundred ninety-four million, seven hundred eighty-eight thousand, four hundred fifty-seven".