205445440 has 56 divisors (see below), whose sum is σ = 491581440. Its totient is φ = 81781248.

The previous prime is 205445431. The next prime is 205445441. The reversal of 205445440 is 44544502.

It is a junction number, because it is equal to n+sod(n) for n = 205445399 and 205445408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205445441) 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 7 ways as a sum of consecutive naturals, for example, 69921 + ... + 72799.

It is an arithmetic number, because the mean of its divisors is an integer number (8778240).

Almost surely, 2^205445440 is an apocalyptic number.

205445440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205445440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (245790720).

205445440 is an abundant number, since it is smaller than the sum of its proper divisors (286136000).

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

205445440 is a wasteful number, since it uses less digits than its factorization.

205445440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3119 (or 3109 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 28.

The square root of 205445440 is about 14333.3680619734. The cubic root of 205445440 is about 590.0636147054.

Adding to 205445440 its reverse (44544502), we get a palindrome (249989942).

The spelling of 205445440 in words is "two hundred five million, four hundred forty-five thousand, four hundred forty".