664841564587 has 4 divisors (see below), whose sum is σ = 664860773880. Its totient is φ = 664822355296.

The previous prime is 664841564551. The next prime is 664841564599. The reversal of 664841564587 is 785465148466.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 785465148466 = 2 ⋅392732574233.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664841564587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664841564537) 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, 9552637 + ... + 9621982.

It is an arithmetic number, because the mean of its divisors is an integer number (166215193470).

Almost surely, 2^664841564587 is an apocalyptic number.

664841564587 is a deficient number, since it is larger than the sum of its proper divisors (19209293).

664841564587 is a wasteful number, since it uses less digits than its factorization.

664841564587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19209292.

The product of its digits is 154828800, while the sum is 64.

The spelling of 664841564587 in words is "six hundred sixty-four billion, eight hundred forty-one million, five hundred sixty-four thousand, five hundred eighty-seven".