664542252 has 192 divisors, whose sum is σ = 2016000000. Its totient is φ = 187168320.

The previous prime is 664542251. The next prime is 664542269. The reversal of 664542252 is 252245466.

664542252 is a `hidden beast` number, since 6 + 64 + 542 + 2 + 52 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (664542251) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1331499 + ... + 1331997.

It is an arithmetic number, because the mean of its divisors is an integer number (10500000).

Almost surely, 2^664542252 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 664542252, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1008000000).

664542252 is an abundant number, since it is smaller than the sum of its proper divisors (1351457748).

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

664542252 is a wasteful number, since it uses less digits than its factorization.

664542252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601 (or 593 counting only the distinct ones).

The product of its digits is 115200, while the sum is 36.

The square root of 664542252 is about 25778.7170355703. The cubic root of 664542252 is about 872.6515537645.

The spelling of 664542252 in words is "six hundred sixty-four million, five hundred forty-two thousand, two hundred fifty-two".