64724509 has 2 divisors, whose sum is σ = 64724510. Its totient is φ = 64724508.

The previous prime is 64724447. The next prime is 64724521. The reversal of 64724509 is 90542746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53144100 + 11580409 = 7290^2 + 3403^2 .

It is a cyclic number.

It is not a de Polignac number, because 64724509 - 2¹⁵ = 64691741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64724809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32362254 + 32362255.

It is an arithmetic number, because the mean of its divisors is an integer number (32362255).

Almost surely, 2^64724509 is an apocalyptic number.

It is an amenable number.

64724509 is a deficient number, since it is larger than the sum of its proper divisors (1).

64724509 is an equidigital number, since it uses as much as digits as its factorization.

64724509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 64724509 is about 8045.1543801222. The cubic root of 64724509 is about 401.5037336290.

The spelling of 64724509 in words is "sixty-four million, seven hundred twenty-four thousand, five hundred nine".