3640720 has 40 divisors (see below), whose sum is σ = 8965944. Its totient is φ = 1370112.

The previous prime is 3640717. The next prime is 3640753. The reversal of 3640720 is 270463.

3640720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 76176 + 3564544 = 276^2 + 1888^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 3640691 and 3640700.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22 + ... + 2698.

Almost surely, 2^3640720 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 3640720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4482972).

3640720 is an abundant number, since it is smaller than the sum of its proper divisors (5325224).

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

3640720 is a wasteful number, since it uses less digits than its factorization.

3640720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2707 (or 2701 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 3640720 is about 1908.0670847745. The cubic root of 3640720 is about 153.8375754191.

The spelling of 3640720 in words is "three million, six hundred forty thousand, seven hundred twenty".