9916421771 has 2 divisors, whose sum is σ = 9916421772. Its totient is φ = 9916421770.

The previous prime is 9916421731. The next prime is 9916421777. The reversal of 9916421771 is 1771246199.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1771246199) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9916421771 - 2⁶ = 9916421707 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (9916421777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4958210885 + 4958210886.

It is an arithmetic number, because the mean of its divisors is an integer number (4958210886).

Almost surely, 2^9916421771 is an apocalyptic number.

9916421771 is a deficient number, since it is larger than the sum of its proper divisors (1).

9916421771 is an equidigital number, since it uses as much as digits as its factorization.

9916421771 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 47.

The square root of 9916421771 is about 99581.2320219026. The cubic root of 9916421771 is about 2148.4157625175.

The spelling of 9916421771 in words is "nine billion, nine hundred sixteen million, four hundred twenty-one thousand, seven hundred seventy-one".