664350624 has 216 divisors, whose sum is σ = 2218376160. Its totient is φ = 188036352.

The previous prime is 664350613. The next prime is 664350641. The reversal of 664350624 is 426053466.

664350624 is a `hidden beast` number, since 6 + 643 + 5 + 0 + 6 + 2 + 4 = 666.

664350624 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 25775²-1.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2525917 + ... + 2526179.

It is an arithmetic number, because the mean of its divisors is an integer number (10270260).

Almost surely, 2^664350624 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 664350624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1109188080).

664350624 is an abundant number, since it is smaller than the sum of its proper divisors (1554025536).

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

664350624 is a wasteful number, since it uses less digits than its factorization.

664350624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472 (or 454 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 664350624 is about 25774.9999806014. Note that the first 4 decimals coincide. The cubic root of 664350624 is about 872.5676661724.

The spelling of 664350624 in words is "six hundred sixty-four million, three hundred fifty thousand, six hundred twenty-four".