531664640 has 144 divisors (see below), whose sum is σ = 1390737600. Its totient is φ = 193560576.

The previous prime is 531664633. The next prime is 531664649. The reversal of 531664640 is 46466135.

It is a self number, because there is not a number n which added to its sum of digits gives 531664640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (531664649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1480781 + ... + 1481139.

It is an arithmetic number, because the mean of its divisors is an integer number (9657900).

Almost surely, 2^531664640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 531664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (695368800).

531664640 is an abundant number, since it is smaller than the sum of its proper divisors (859072960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

531664640 is a wasteful number, since it uses less digits than its factorization.

531664640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 482 (or 468 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 531664640 is about 23057.8541933112. The cubic root of 531664640 is about 810.1136049569.

The spelling of 531664640 in words is "five hundred thirty-one million, six hundred sixty-four thousand, six hundred forty".