205401440 has 24 divisors (see below), whose sum is σ = 485261280. Its totient is φ = 82160512.

The previous prime is 205401433. The next prime is 205401481. The reversal of 205401440 is 44104502.

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

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 641720 + ... + 642039.

It is an arithmetic number, because the mean of its divisors is an integer number (20219220).

Almost surely, 2^205401440 is an apocalyptic number.

205401440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205401440 is an abundant number, since it is smaller than the sum of its proper divisors (279859840).

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

205401440 is a wasteful number, since it uses less digits than its factorization.

205401440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1283774 (or 1283766 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 205401440 is about 14331.8330997818. The cubic root of 205401440 is about 590.0214872956.

Adding to 205401440 its reverse (44104502), we get a palindrome (249505942).

The spelling of 205401440 in words is "two hundred five million, four hundred one thousand, four hundred forty".