64644588009 has 9 divisors (see below), whose sum is σ = 93376617789. Its totient is φ = 43095883500.

The previous prime is 64644587989. The next prime is 64644588011. The reversal of 64644588009 is 90088544646.

The square root of 64644588009 is 254253.

It is a perfect power (a square), and thus also a powerful number.

64644588009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 64644588009 - 2¹³ = 64644579817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64644588089) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 720384 + ... + 805134.

Almost surely, 2^64644588009 is an apocalyptic number.

64644588009 is the 254253-rd square number.

64644588009 is the 127127-th centered octagonal number.

It is an amenable number.

64644588009 is a deficient number, since it is larger than the sum of its proper divisors (28732029780).

64644588009 is an frugal number, since it uses more digits than its factorization.

64644588009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169508 (or 84754 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 54.

It can be divided in two parts, 64644 and 588009, that added together give a triangular number (652653 = T₁₁₄₂).

The spelling of 64644588009 in words is "sixty-four billion, six hundred forty-four million, five hundred eighty-eight thousand, nine".