20320000645 has 16 divisors (see below), whose sum is σ = 28067921280. Its totient is φ = 13833468864.

The previous prime is 20320000643. The next prime is 20320000663. The reversal of 20320000645 is 54600002302.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20320000645 - 2¹ = 20320000643 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20320000643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2083522 + ... + 2093251.

It is an arithmetic number, because the mean of its divisors is an integer number (1754245080).

Almost surely, 2^20320000645 is an apocalyptic number.

It is an amenable number.

20320000645 is a deficient number, since it is larger than the sum of its proper divisors (7747920635).

20320000645 is a wasteful number, since it uses less digits than its factorization.

20320000645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4176924.

The product of its (nonzero) digits is 1440, while the sum is 22.

Adding to 20320000645 its reverse (54600002302), we get a palindrome (74920002947).

The spelling of 20320000645 in words is "twenty billion, three hundred twenty million, six hundred forty-five", and thus it is an aban number.