205304240 has 40 divisors (see below), whose sum is σ = 505414080. Its totient is φ = 77290496.

The previous prime is 205304171. The next prime is 205304243. The reversal of 205304240 is 42403502.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (205304243) 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, 74120 + ... + 76839.

It is an arithmetic number, because the mean of its divisors is an integer number (12635352).

Almost surely, 2^205304240 is an apocalyptic number.

205304240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205304240 is an abundant number, since it is smaller than the sum of its proper divisors (300109840).

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

205304240 is a wasteful number, since it uses less digits than its factorization.

205304240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150989 (or 150983 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 20.

The square root of 205304240 is about 14328.4416459013. The cubic root of 205304240 is about 589.9284026880.

Adding to 205304240 its reverse (42403502), we get a palindrome (247707742).

The spelling of 205304240 in words is "two hundred five million, three hundred four thousand, two hundred forty".