644466045 has 8 divisors (see below), whose sum is σ = 1031145696. Its totient is φ = 343715216.

The previous prime is 644466041. The next prime is 644466047. The reversal of 644466045 is 540664446.

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 644466045 - 2² = 644466041 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 644465994 and 644466012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644466041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21482187 + ... + 21482216.

It is an arithmetic number, because the mean of its divisors is an integer number (128893212).

Almost surely, 2^644466045 is an apocalyptic number.

It is an amenable number.

644466045 is a deficient number, since it is larger than the sum of its proper divisors (386679651).

644466045 is a wasteful number, since it uses less digits than its factorization.

644466045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42964411.

The product of its (nonzero) digits is 276480, while the sum is 39.

The square root of 644466045 is about 25386.3357930994. The cubic root of 644466045 is about 863.7737734505.

The spelling of 644466045 in words is "six hundred forty-four million, four hundred sixty-six thousand, forty-five".