205144420 has 24 divisors (see below), whose sum is σ = 463942584. Its totient is φ = 75745536.

The previous prime is 205144417. The next prime is 205144421. The reversal of 205144420 is 24441502.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 19149376 + 185995044 = 4376^2 + 13638^2 .

It is a junction number, because it is equal to n+sod(n) for n = 205144391 and 205144400.

It is not an unprimeable number, because it can be changed into a prime (205144421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 394249 + ... + 394768.

It is an arithmetic number, because the mean of its divisors is an integer number (19330941).

Almost surely, 2^205144420 is an apocalyptic number.

205144420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205144420 is an abundant number, since it is smaller than the sum of its proper divisors (258798164).

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

205144420 is a wasteful number, since it uses less digits than its factorization.

205144420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789039 (or 789037 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 205144420 is about 14322.8635405075. The cubic root of 205144420 is about 589.7752854853.

Adding to 205144420 its reverse (24441502), we get a palindrome (229585922).

The spelling of 205144420 in words is "two hundred five million, one hundred forty-four thousand, four hundred twenty".