6664320 has 192 divisors, whose sum is σ = 25061400. Its totient is φ = 1622016.

The previous prime is 6664309. The next prime is 6664321. The reversal of 6664320 is 234666.

It can be written as a sum of positive squares in 4 ways, for example, as 3069504 + 3594816 = 1752^2 + 1896^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×6664320² = 88826322124800, which contains 22 as substring.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (6664321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 74836 + ... + 74924.

Almost surely, 2^6664320 is an apocalyptic number.

6664320 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 6664320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12530700).

6664320 is an abundant number, since it is smaller than the sum of its proper divisors (18397080).

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

6664320 is a wasteful number, since it uses less digits than its factorization.

6664320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 6664320 is about 2581.5344274288. The cubic root of 6664320 is about 188.1851202058.

Adding to 6664320 its reverse (234666), we get a palindrome (6898986).

The spelling of 6664320 in words is "six million, six hundred sixty-four thousand, three hundred twenty".