6399400 has 72 divisors (see below), whose sum is σ = 17334270. Its totient is φ = 2190720.

The previous prime is 6399397. The next prime is 6399427. The reversal of 6399400 is 49936.

It can be written as a sum of positive squares in 3 ways, for example, as 3896676 + 2502724 = 1974^2 + 1582^2 .

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 9474 + ... + 10126.

Almost surely, 2^6399400 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 6399400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8667135).

6399400 is an abundant number, since it is smaller than the sum of its proper divisors (10934870).

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

6399400 is a wasteful number, since it uses less digits than its factorization.

6399400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 6399400 is about 2529.7035399430. The cubic root of 6399400 is about 185.6577511771.

The spelling of 6399400 in words is "six million, three hundred ninety-nine thousand, four hundred".