664544531 has 8 divisors (see below), whose sum is σ = 780006240. Its totient is φ = 554214528.

The previous prime is 664544521. The next prime is 664544537. The reversal of 664544531 is 135445466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 664544531 - 2¹⁰ = 664543507 is a prime.

It is a super-2 number, since 2×664544531² = 883238867364019922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664544537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1282646 + ... + 1283163.

It is an arithmetic number, because the mean of its divisors is an integer number (97500780).

Almost surely, 2^664544531 is an apocalyptic number.

664544531 is a deficient number, since it is larger than the sum of its proper divisors (115461709).

664544531 is a wasteful number, since it uses less digits than its factorization.

664544531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2565853.

The product of its digits is 172800, while the sum is 38.

The square root of 664544531 is about 25778.7612386631. The cubic root of 664544531 is about 872.6525513287.

Adding to 664544531 its reverse (135445466), we get a palindrome (799989997).

The spelling of 664544531 in words is "six hundred sixty-four million, five hundred forty-four thousand, five hundred thirty-one".