664056559 has 4 divisors (see below), whose sum is σ = 664189960. Its totient is φ = 663923160.

The previous prime is 664056551. The next prime is 664056577. The reversal of 664056559 is 955650466.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 955650466 = 2 ⋅477825233.

It is a cyclic number.

It is not a de Polignac number, because 664056559 - 2³ = 664056551 is a prime.

It is a super-2 number, since 2×664056559² = 881942227101840962, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664056551) 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, 58932 + ... + 69289.

It is an arithmetic number, because the mean of its divisors is an integer number (166047490).

Almost surely, 2^664056559 is an apocalyptic number.

664056559 is a deficient number, since it is larger than the sum of its proper divisors (133401).

664056559 is a wasteful number, since it uses less digits than its factorization.

664056559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133400.

The product of its (nonzero) digits is 972000, while the sum is 46.

The square root of 664056559 is about 25769.2948875207. The cubic root of 664056559 is about 872.4389041053.

The spelling of 664056559 in words is "six hundred sixty-four million, fifty-six thousand, five hundred fifty-nine".