9993091897 has 2 divisors, whose sum is σ = 9993091898. Its totient is φ = 9993091896.

The previous prime is 9993091853. The next prime is 9993091921. The reversal of 9993091897 is 7981903999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9059422761 + 933669136 = 95181^2 + 30556^2 .

It is an emirp because it is prime and its reverse (7981903999) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9993091897 is a prime.

It is not a weakly prime, because it can be changed into another prime (9993091697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4996545948 + 4996545949.

It is an arithmetic number, because the mean of its divisors is an integer number (4996545949).

Almost surely, 2^9993091897 is an apocalyptic number.

It is an amenable number.

9993091897 is a deficient number, since it is larger than the sum of its proper divisors (1).

9993091897 is an equidigital number, since it uses as much as digits as its factorization.

9993091897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9920232, while the sum is 64.

The square root of 9993091897 is about 99965.4535177028. The cubic root of 9993091897 is about 2153.9384738591.

The spelling of 9993091897 in words is "nine billion, nine hundred ninety-three million, ninety-one thousand, eight hundred ninety-seven".