2640220 has 36 divisors (see below), whose sum is σ = 6099912. Its totient is φ = 959200.

The previous prime is 2640217. The next prime is 2640227. The reversal of 2640220 is 220462.

It is a junction number, because it is equal to n+sod(n) for n = 2640194 and 2640203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2640227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1875 + ... + 2965.

It is an arithmetic number, because the mean of its divisors is an integer number (169442).

2^2640220 is an apocalyptic number.

2640220 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 2640220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3049956).

2640220 is an abundant number, since it is smaller than the sum of its proper divisors (3459692).

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

2640220 is a wasteful number, since it uses less digits than its factorization.

2640220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1122 (or 1109 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 2640220 is about 1624.8753798369. The cubic root of 2640220 is about 138.2123036176.

Adding to 2640220 its reverse (220462), we get a palindrome (2860682).

The spelling of 2640220 in words is "two million, six hundred forty thousand, two hundred twenty".