205115440 has 20 divisors (see below), whose sum is σ = 476893584. Its totient is φ = 82046144.

The previous prime is 205115423. The next prime is 205115501. The reversal of 205115440 is 44511502.

It is a tau number, because it is divible by the number of its divisors (20).

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1281892 + ... + 1282051.

Almost surely, 2^205115440 is an apocalyptic number.

205115440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205115440 is an abundant number, since it is smaller than the sum of its proper divisors (271778144).

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

205115440 is a wasteful number, since it uses less digits than its factorization.

205115440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2563956 (or 2563950 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 205115440 is about 14321.8518355693. The cubic root of 205115440 is about 589.7475123802.

Adding to 205115440 its reverse (44511502), we get a palindrome (249626942).

The spelling of 205115440 in words is "two hundred five million, one hundred fifteen thousand, four hundred forty".