8509973 has 2 divisors, whose sum is σ = 8509974. Its totient is φ = 8509972.

The previous prime is 8509939. The next prime is 8509981. The reversal of 8509973 is 3799058.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5098564 + 3411409 = 2258^2 + 1847^2 .

It is a cyclic number.

It is not a de Polignac number, because 8509973 - 2⁶ = 8509909 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 8509973.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8509933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4254986 + 4254987.

It is an arithmetic number, because the mean of its divisors is an integer number (4254987).

Almost surely, 2^8509973 is an apocalyptic number.

It is an amenable number.

8509973 is a deficient number, since it is larger than the sum of its proper divisors (1).

8509973 is an equidigital number, since it uses as much as digits as its factorization.

8509973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68040, while the sum is 41.

The square root of 8509973 is about 2917.1858014189. The cubic root of 8509973 is about 204.1625402655.

Subtracting from 8509973 its reverse (3799058), we obtain a triangular number (4710915 = T₃₀₆₉).

The spelling of 8509973 in words is "eight million, five hundred nine thousand, nine hundred seventy-three".