664819600 has 120 divisors (see below), whose sum is σ = 1682749440. Its totient is φ = 251919360.

The previous prime is 664819591. The next prime is 664819601. The reversal of 664819600 is 6918466.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (664819601) 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 23 ways as a sum of consecutive naturals, for example, 1168116 + ... + 1168684.

It is an arithmetic number, because the mean of its divisors is an integer number (14022912).

Almost surely, 2^664819600 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 664819600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (841374720).

664819600 is an abundant number, since it is smaller than the sum of its proper divisors (1017929840).

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

664819600 is a wasteful number, since it uses less digits than its factorization.

664819600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737 (or 726 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 664819600 is about 25784.0958732316. The cubic root of 664819600 is about 872.7729378199.

The spelling of 664819600 in words is "six hundred sixty-four million, eight hundred nineteen thousand, six hundred".