664560445 has 4 divisors (see below), whose sum is σ = 797472540. Its totient is φ = 531648352.

The previous prime is 664560427. The next prime is 664560451. The reversal of 664560445 is 544065466.

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 117094041 + 547466404 = 10821^2 + 23398^2 .

It is a cyclic number.

It is not a de Polignac number, because 664560445 - 2⁹ = 664559933 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 664560398 and 664560407.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 66456040 + ... + 66456049.

It is an arithmetic number, because the mean of its divisors is an integer number (199368135).

Almost surely, 2^664560445 is an apocalyptic number.

It is an amenable number.

664560445 is a deficient number, since it is larger than the sum of its proper divisors (132912095).

664560445 is a wasteful number, since it uses less digits than its factorization.

664560445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132912094.

The product of its (nonzero) digits is 345600, while the sum is 40.

The square root of 664560445 is about 25779.0699017633. The cubic root of 664560445 is about 872.6595171432.

The spelling of 664560445 in words is "six hundred sixty-four million, five hundred sixty thousand, four hundred forty-five".