64344640561 has 8 divisors (see below), whose sum is σ = 66566364480. Its totient is φ = 62123112912.

The previous prime is 64344640487. The next prime is 64344640571. The reversal of 64344640561 is 16504644346.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64344640561 - 2¹⁹ = 64344116273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64344640571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 994156 + ... + 1056898.

It is an arithmetic number, because the mean of its divisors is an integer number (8320795560).

Almost surely, 2^64344640561 is an apocalyptic number.

It is an amenable number.

64344640561 is a deficient number, since it is larger than the sum of its proper divisors (2221723919).

64344640561 is a wasteful number, since it uses less digits than its factorization.

64344640561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98135.

The product of its (nonzero) digits is 829440, while the sum is 43.

The spelling of 64344640561 in words is "sixty-four billion, three hundred forty-four million, six hundred forty thousand, five hundred sixty-one".