6664400 has 30 divisors (see below), whose sum is σ = 16012182. Its totient is φ = 2665600.

The previous prime is 6664387. The next prime is 6664417. The reversal of 6664400 is 44666.

It can be written as a sum of positive squares in 3 ways, for example, as 394384 + 6270016 = 628^2 + 2504^2 .

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 6664400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7931 + ... + 8730.

Almost surely, 2^6664400 is an apocalyptic number.

It is an amenable number.

6664400 is an abundant number, since it is smaller than the sum of its proper divisors (9347782).

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

6664400 is a wasteful number, since it uses less digits than its factorization.

6664400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16679 (or 16668 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 6664400 is about 2581.5499220430. The cubic root of 6664400 is about 188.1858732083.

The spelling of 6664400 in words is "six million, six hundred sixty-four thousand, four hundred".