6821456 has 30 divisors (see below), whose sum is σ = 13960602. Its totient is φ = 3228480.

The previous prime is 6821443. The next prime is 6821461. The reversal of 6821456 is 6541286.

It can be written as a sum of positive squares in only one way, i.e., 6677056 + 144400 = 2584^2 + 380^2 .

It is a super-3 number, since 3×6821456³ (a number of 21 digits) contains 333 as substring.

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, 5186 + ... + 6366.

Almost surely, 2^6821456 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 6821456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6980301).

6821456 is an abundant number, since it is smaller than the sum of its proper divisors (7139146).

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

6821456 is a wasteful number, since it uses less digits than its factorization.

6821456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1227 (or 1202 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 6821456 is about 2611.7917221708. The cubic root of 6821456 is about 189.6526988882.

The spelling of 6821456 in words is "six million, eight hundred twenty-one thousand, four hundred fifty-six".