20420244 has 36 divisors (see below), whose sum is σ = 55589716. Its totient is φ = 6283008.

The previous prime is 20420243. The next prime is 20420287. The reversal of 20420244 is 44202402.

20420244 is a `hidden beast` number, since 2 + 0 + 420 + 244 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11492100 + 8928144 = 3390^2 + 2988^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20420243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21349 + ... + 22284.

Almost surely, 2^20420244 is an apocalyptic number.

It is an amenable number.

20420244 is an abundant number, since it is smaller than the sum of its proper divisors (35169472).

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

20420244 is a wasteful number, since it uses less digits than its factorization.

20420244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43656 (or 43651 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 20420244 is about 4518.8764090203. The cubic root of 20420244 is about 273.3297950497.

Adding to 20420244 its reverse (44202402), we get a palindrome (64622646).

The spelling of 20420244 in words is "twenty million, four hundred twenty thousand, two hundred forty-four".