6816400 has 30 divisors (see below), whose sum is σ = 16377362. Its totient is φ = 2726400.

The previous prime is 6816367. The next prime is 6816401. The reversal of 6816400 is 46186.

It can be written as a sum of positive squares in 3 ways, for example, as 1507984 + 5308416 = 1228^2 + 2304^2 .

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

It is a nialpdrome in base 5.

It is not an unprimeable number, because it can be changed into a prime (6816401) 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, 8121 + ... + 8920.

Almost surely, 2^6816400 is an apocalyptic number.

It is an amenable number.

6816400 is an abundant number, since it is smaller than the sum of its proper divisors (9560962).

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

6816400 is a wasteful number, since it uses less digits than its factorization.

6816400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17059 (or 17048 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 6816400 is about 2610.8236248357. The cubic root of 6816400 is about 189.6058310324.

The spelling of 6816400 in words is "six million, eight hundred sixteen thousand, four hundred".