64844809 has 4 divisors (see below), whose sum is σ = 64864404. Its totient is φ = 64825216.

The previous prime is 64844807. The next prime is 64844827. The reversal of 64844809 is 90844846.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 62805625 + 2039184 = 7925^2 + 1428^2 .

It is a cyclic number.

It is not a de Polignac number, because 64844809 - 2¹ = 64844807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64844807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3472 + ... + 11905.

It is an arithmetic number, because the mean of its divisors is an integer number (16216101).

Almost surely, 2^64844809 is an apocalyptic number.

It is an amenable number.

64844809 is a deficient number, since it is larger than the sum of its proper divisors (19595).

64844809 is a wasteful number, since it uses less digits than its factorization.

64844809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19594.

The product of its (nonzero) digits is 221184, while the sum is 43.

The square root of 64844809 is about 8052.6274594073. The cubic root of 64844809 is about 401.7523308812.

The spelling of 64844809 in words is "sixty-four million, eight hundred forty-four thousand, eight hundred nine".