205251440 has 20 divisors (see below), whose sum is σ = 477209784. Its totient is φ = 82100544.

The previous prime is 205251439. The next prime is 205251463. The reversal of 205251440 is 44152502.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1282742 + ... + 1282901.

Almost surely, 2^205251440 is an apocalyptic number.

205251440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205251440 is an abundant number, since it is smaller than the sum of its proper divisors (271958344).

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

205251440 is a wasteful number, since it uses less digits than its factorization.

205251440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2565656 (or 2565650 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 205251440 is about 14326.5990381528. The cubic root of 205251440 is about 589.8778258948.

The spelling of 205251440 in words is "two hundred five million, two hundred fifty-one thousand, four hundred forty".