9391427681 has 2 divisors, whose sum is σ = 9391427682. Its totient is φ = 9391427680.

The previous prime is 9391427677. The next prime is 9391427699. The reversal of 9391427681 is 1867241939.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9334651456 + 56776225 = 96616^2 + 7535^2 .

It is an emirp because it is prime and its reverse (1867241939) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9391427681 - 2² = 9391427677 is a prime.

It is a super-2 number, since 2×9391427681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9391427611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4695713840 + 4695713841.

It is an arithmetic number, because the mean of its divisors is an integer number (4695713841).

Almost surely, 2^9391427681 is an apocalyptic number.

It is an amenable number.

9391427681 is a deficient number, since it is larger than the sum of its proper divisors (1).

9391427681 is an equidigital number, since it uses as much as digits as its factorization.

9391427681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 50.

The square root of 9391427681 is about 96909.3787050562. The cubic root of 9391427681 is about 2109.8125572654.

The spelling of 9391427681 in words is "nine billion, three hundred ninety-one million, four hundred twenty-seven thousand, six hundred eighty-one".