2806440 has 128 divisors (see below), whose sum is σ = 10402560. Its totient is φ = 589824.

The previous prime is 2806439. The next prime is 2806457. The reversal of 2806440 is 446082.

It is a super-2 number, since 2×2806440² = 15752210947200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 2806440.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10792 + ... + 11048.

It is an arithmetic number, because the mean of its divisors is an integer number (81270).

2^2806440 is an apocalyptic number.

2806440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2806440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5201280).

2806440 is an abundant number, since it is smaller than the sum of its proper divisors (7596120).

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

2806440 is a wasteful number, since it uses less digits than its factorization.

2806440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 2806440 is about 1675.2432659169. The cubic root of 2806440 is about 141.0539504826.

The spelling of 2806440 in words is "two million, eight hundred six thousand, four hundred forty".