2321640 has 48 divisors (see below), whose sum is σ = 7546500. Its totient is φ = 619008.

The previous prime is 2321623. The next prime is 2321647. The reversal of 2321640 is 461232.

It is a happy number.

2321640 is a `hidden beast` number, since 2 + 3 + 21 + 640 = 666.

2321640 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 2 ways, for example, as 2196324 + 125316 = 1482^2 + 354^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (2321647) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 2865 + ... + 3584.

2^2321640 is an apocalyptic number.

2321640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2321640 is an abundant number, since it is smaller than the sum of its proper divisors (5224860).

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

2321640 is a wasteful number, since it uses less digits than its factorization.

2321640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6466 (or 6459 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 2321640 is about 1523.6928824406. The cubic root of 2321640 is about 132.4133051010.

Adding to 2321640 its reverse (461232), we get a palindrome (2782872).

The spelling of 2321640 in words is "two million, three hundred twenty-one thousand, six hundred forty".