64634509 has 2 divisors, whose sum is σ = 64634510. Its totient is φ = 64634508.

The previous prime is 64634497. The next prime is 64634519. The reversal of 64634509 is 90543646.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51696100 + 12938409 = 7190^2 + 3597^2 .

It is a cyclic number.

It is not a de Polignac number, because 64634509 - 2¹⁷ = 64503437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64634519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32317254 + 32317255.

It is an arithmetic number, because the mean of its divisors is an integer number (32317255).

Almost surely, 2^64634509 is an apocalyptic number.

It is an amenable number.

64634509 is a deficient number, since it is larger than the sum of its proper divisors (1).

64634509 is an equidigital number, since it uses as much as digits as its factorization.

64634509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 64634509 is about 8039.5590053186. The cubic root of 64634509 is about 401.3175491457.

The spelling of 64634509 in words is "sixty-four million, six hundred thirty-four thousand, five hundred nine".