2636640 has 72 divisors (see below), whose sum is σ = 9002448. Its totient is φ = 702720.

The previous prime is 2636633. The next prime is 2636663. The reversal of 2636640 is 466362.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 525 + ... + 2355.

It is an arithmetic number, because the mean of its divisors is an integer number (125034).

2^2636640 is an apocalyptic number.

2636640 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 2636640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4501224).

2636640 is an abundant number, since it is smaller than the sum of its proper divisors (6365808).

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

2636640 is a wasteful number, since it uses less digits than its factorization.

2636640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1852 (or 1841 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 2636640 is about 1623.7733832035. The cubic root of 2636640 is about 138.1498058136.

It can be divided in two parts, 263 and 6640, that added together give a triangular number (6903 = T₁₁₇).

The spelling of 2636640 in words is "two million, six hundred thirty-six thousand, six hundred forty".