20320641 has 24 divisors (see below), whose sum is σ = 32419296. Its totient is φ = 12162240.

The previous prime is 20320609. The next prime is 20320669. The reversal of 20320641 is 14602302.

It is a happy number.

20320641 is a `hidden beast` number, since 2 + 0 + 3 + 20 + 641 = 666.

It is not a de Polignac number, because 20320641 - 2⁵ = 20320609 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20320241) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6981 + ... + 9453.

It is an arithmetic number, because the mean of its divisors is an integer number (1350804).

Almost surely, 2^20320641 is an apocalyptic number.

It is an amenable number.

20320641 is a deficient number, since it is larger than the sum of its proper divisors (12098655).

20320641 is a wasteful number, since it uses less digits than its factorization.

20320641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2573 (or 2570 counting only the distinct ones).

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

The square root of 20320641 is about 4507.8421667135. The cubic root of 20320641 is about 272.8846672995.

Adding to 20320641 its reverse (14602302), we get a palindrome (34922943).

The spelling of 20320641 in words is "twenty million, three hundred twenty thousand, six hundred forty-one".