438581664 has 144 divisors (see below), whose sum is σ = 1320725952. Its totient is φ = 137769984.

The previous prime is 438581659. The next prime is 438581677. The reversal of 438581664 is 466185834.

438581664 is a `hidden beast` number, since 4 + 3 + 8 + 581 + 6 + 64 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-4 number, since 4×438581664⁴ (a number of 36 digits) contains 4444 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 483099 + ... + 484005.

It is an arithmetic number, because the mean of its divisors is an integer number (9171708).

Almost surely, 2^438581664 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 438581664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (660362976).

438581664 is an abundant number, since it is smaller than the sum of its proper divisors (882144288).

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

438581664 is a wasteful number, since it uses less digits than its factorization.

438581664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019 (or 1008 counting only the distinct ones).

The product of its digits is 552960, while the sum is 45.

The square root of 438581664 is about 20942.3414163746. The cubic root of 438581664 is about 759.7723602623.

The spelling of 438581664 in words is "four hundred thirty-eight million, five hundred eighty-one thousand, six hundred sixty-four".