664560557533 has 4 divisors (see below), whose sum is σ = 664566041020. Its totient is φ = 664555074048.

The previous prime is 664560557503. The next prime is 664560557539. The reversal of 664560557533 is 335755065466.

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 240984773604 + 423575783929 = 490902^2 + 650827^2 .

It is a cyclic number.

It is not a de Polignac number, because 664560557533 - 2²⁹ = 664023686621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664560557539) 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, 2555748 + ... + 2803741.

It is an arithmetic number, because the mean of its divisors is an integer number (166141510255).

Almost surely, 2^664560557533 is an apocalyptic number.

It is an amenable number.

664560557533 is a deficient number, since it is larger than the sum of its proper divisors (5483487).

664560557533 is a wasteful number, since it uses less digits than its factorization.

664560557533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5483486.

The product of its (nonzero) digits is 34020000, while the sum is 55.

The spelling of 664560557533 in words is "six hundred sixty-four billion, five hundred sixty million, five hundred fifty-seven thousand, five hundred thirty-three".