65984509 has 2 divisors, whose sum is σ = 65984510. Its totient is φ = 65984508.

The previous prime is 65984507. The next prime is 65984521. The reversal of 65984509 is 90548956.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57002500 + 8982009 = 7550^2 + 2997^2 .

It is a cyclic number.

It is not a de Polignac number, because 65984509 - 2¹ = 65984507 is a prime.

It is a super-3 number, since 3×65984509³ (a number of 24 digits) contains 333 as substring.

Together with 65984507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65984507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32992254 + 32992255.

It is an arithmetic number, because the mean of its divisors is an integer number (32992255).

Almost surely, 2^65984509 is an apocalyptic number.

It is an amenable number.

65984509 is a deficient number, since it is larger than the sum of its proper divisors (1).

65984509 is an equidigital number, since it uses as much as digits as its factorization.

65984509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 388800, while the sum is 46.

The square root of 65984509 is about 8123.0849435421. The cubic root of 65984509 is about 404.0923819876.

The spelling of 65984509 in words is "sixty-five million, nine hundred eighty-four thousand, five hundred nine".