9917438081 has 2 divisors, whose sum is σ = 9917438082. Its totient is φ = 9917438080.

The previous prime is 9917438033. The next prime is 9917438101. The reversal of 9917438081 is 1808347199.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8881177600 + 1036260481 = 94240^2 + 32191^2 .

It is a cyclic number.

It is not a de Polignac number, because 9917438081 - 2¹⁸ = 9917175937 is a prime.

It is a super-2 number, since 2×9917438081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9917438681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4958719040 + 4958719041.

It is an arithmetic number, because the mean of its divisors is an integer number (4958719041).

Almost surely, 2^9917438081 is an apocalyptic number.

It is an amenable number.

9917438081 is a deficient number, since it is larger than the sum of its proper divisors (1).

9917438081 is an equidigital number, since it uses as much as digits as its factorization.

9917438081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 50.

The square root of 9917438081 is about 99586.3348105552. The cubic root of 9917438081 is about 2148.4891553161.

The spelling of 9917438081 in words is "nine billion, nine hundred seventeen million, four hundred thirty-eight thousand, eighty-one".