9973545809 has 2 divisors, whose sum is σ = 9973545810. Its totient is φ = 9973545808.

The previous prime is 9973545793. The next prime is 9973545847. The reversal of 9973545809 is 9085453799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9795456784 + 178089025 = 98972^2 + 13345^2 .

It is an emirp because it is prime and its reverse (9085453799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9973545809 - 2⁴ = 9973545793 is a prime.

It is not a weakly prime, because it can be changed into another prime (9973545899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4986772904 + 4986772905.

It is an arithmetic number, because the mean of its divisors is an integer number (4986772905).

Almost surely, 2^9973545809 is an apocalyptic number.

It is an amenable number.

9973545809 is a deficient number, since it is larger than the sum of its proper divisors (1).

9973545809 is an equidigital number, since it uses as much as digits as its factorization.

9973545809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12247200, while the sum is 59.

The square root of 9973545809 is about 99867.6414510726. The cubic root of 9973545809 is about 2152.5332180886.

The spelling of 9973545809 in words is "nine billion, nine hundred seventy-three million, five hundred forty-five thousand, eight hundred nine".