20944985 has 4 divisors (see below), whose sum is σ = 25133988. Its totient is φ = 16755984.

The previous prime is 20944981. The next prime is 20945039. The reversal of 20944985 is 58944902.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10883401 + 10061584 = 3299^2 + 3172^2 .

It is a cyclic number.

It is not a de Polignac number, because 20944985 - 2² = 20944981 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20944981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2094494 + ... + 2094503.

It is an arithmetic number, because the mean of its divisors is an integer number (6283497).

Almost surely, 2^20944985 is an apocalyptic number.

It is an amenable number.

20944985 is a deficient number, since it is larger than the sum of its proper divisors (4189003).

20944985 is an equidigital number, since it uses as much as digits as its factorization.

20944985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4189002.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 20944985 is about 4576.5691298177. The cubic root of 20944985 is about 275.6512827949.

The spelling of 20944985 in words is "twenty million, nine hundred forty-four thousand, nine hundred eighty-five".