64644303305 has 4 divisors (see below), whose sum is σ = 77573163972. Its totient is φ = 51715442640.

The previous prime is 64644303293. The next prime is 64644303329. The reversal of 64644303305 is 50330344646.

64644303305 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50330344646 = 2 ⋅25165172323.

It can be written as a sum of positive squares in 2 ways, for example, as 9040776889 + 55603526416 = 95083^2 + 235804^2 .

It is not a de Polignac number, because 64644303305 - 2⁸ = 64644303049 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6464430326 + ... + 6464430335.

It is an arithmetic number, because the mean of its divisors is an integer number (19393290993).

Almost surely, 2^64644303305 is an apocalyptic number.

It is an amenable number.

64644303305 is a deficient number, since it is larger than the sum of its proper divisors (12928860667).

64644303305 is a wasteful number, since it uses less digits than its factorization.

64644303305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12928860666.

The product of its (nonzero) digits is 311040, while the sum is 38.

The spelling of 64644303305 in words is "sixty-four billion, six hundred forty-four million, three hundred three thousand, three hundred five".