2621440 has 40 divisors (see below), whose sum is σ = 6291450. Its totient is φ = 1048576.

The previous prime is 2621431. The next prime is 2621447. The reversal of 2621440 is 441262.

It can be written as a sum of positive squares in only one way, i.e., 2359296 + 262144 = 1536^2 + 512^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a nialpdrome in base 4.

It is a zygodrome in base 4.

It is not an unprimeable number, because it can be changed into a prime (2621447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (2) of ones.

In principle, a polygon with 2621440 sides can be constructed with ruler and compass.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 524286 + ... + 524290.

2^2621440 is an apocalyptic number.

2621440 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 2621440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3145725).

2621440 is an abundant number, since it is smaller than the sum of its proper divisors (3670010).

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

2621440 is an frugal number, since it uses more digits than its factorization.

2621440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43 (or 7 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 2621440 is about 1619.0861620062. The cubic root of 2621440 is about 137.8838201620.

The spelling of 2621440 in words is "two million, six hundred twenty-one thousand, four hundred forty".