20445163 has 4 divisors (see below), whose sum is σ = 20460688. Its totient is φ = 20429640.

The previous prime is 20445149. The next prime is 20445179. The reversal of 20445163 is 36154402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20445163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20445143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5583 + ... + 8488.

It is an arithmetic number, because the mean of its divisors is an integer number (5115172).

Almost surely, 2^20445163 is an apocalyptic number.

20445163 is a deficient number, since it is larger than the sum of its proper divisors (15525).

20445163 is a wasteful number, since it uses less digits than its factorization.

20445163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15524.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 20445163 is about 4521.6327803129. The cubic root of 20445163 is about 273.4409320908.

Adding to 20445163 its reverse (36154402), we get a palindrome (56599565).

The spelling of 20445163 in words is "twenty million, four hundred forty-five thousand, one hundred sixty-three".