664042500 has 180 divisors, whose sum is σ = 2289054768. Its totient is φ = 160920000.

The previous prime is 664042469. The next prime is 664042501. The reversal of 664042500 is 5240466.

It is a happy number.

664042500 is a `hidden beast` number, since 6 + 6 + 404 + 250 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (180).

It is not an unprimeable number, because it can be changed into a prime (664042501) 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 59 ways as a sum of consecutive naturals, for example, 246159 + ... + 248841.

Almost surely, 2^664042500 is an apocalyptic number.

664042500 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664042500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1144527384).

664042500 is an abundant number, since it is smaller than the sum of its proper divisors (1625012268).

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

664042500 is a wasteful number, since it uses less digits than its factorization.

664042500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2724 (or 2704 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 664042500 is about 25769.0221001884. The cubic root of 664042500 is about 872.4327471472.

Adding to 664042500 its reverse (5240466), we get a palindrome (669282966).

The spelling of 664042500 in words is "six hundred sixty-four million, forty-two thousand, five hundred".