205431140 has 24 divisors (see below), whose sum is σ = 433823040. Its totient is φ = 81711968.

The previous prime is 205431137. The next prime is 205431181. The reversal of 205431140 is 41134502.

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

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 7 ways as a sum of consecutive naturals, for example, 25112 + ... + 32271.

It is an arithmetic number, because the mean of its divisors is an integer number (18075960).

Almost surely, 2^205431140 is an apocalyptic number.

205431140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205431140 is an abundant number, since it is smaller than the sum of its proper divisors (228391900).

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

205431140 is a wasteful number, since it uses less digits than its factorization.

205431140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57571 (or 57569 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 205431140 is about 14332.8692172921. The cubic root of 205431140 is about 590.0499239570.

Adding to 205431140 its reverse (41134502), we get a palindrome (246565642).

The spelling of 205431140 in words is "two hundred five million, four hundred thirty-one thousand, one hundred forty".