6438400 has 60 divisors (see below), whose sum is σ = 15983352. Its totient is φ = 2570240.

The previous prime is 6438391. The next prime is 6438403. The reversal of 6438400 is 48346.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6438403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12549 + ... + 13051.

Almost surely, 2^6438400 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 6438400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7991676).

6438400 is an abundant number, since it is smaller than the sum of its proper divisors (9544952).

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

6438400 is an equidigital number, since it uses as much as digits as its factorization.

6438400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 531 (or 510 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 6438400 is about 2537.4002443446. The cubic root of 6438400 is about 186.0341402626.

The spelling of 6438400 in words is "six million, four hundred thirty-eight thousand, four hundred".