205251543400 has 96 divisors (see below), whose sum is σ = 513564819480. Its totient is φ = 76004352000.

The previous prime is 205251543391. The next prime is 205251543457. The reversal of 205251543400 is 4345152502.

It can be written as a sum of positive squares in 12 ways, for example, as 19874796484 + 185376746916 = 140978^2 + 430554^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 287421 + ... + 702220.

Almost surely, 2^205251543400 is an apocalyptic number.

205251543400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205251543400 is an abundant number, since it is smaller than the sum of its proper divisors (308313276080).

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

205251543400 is a wasteful number, since it uses less digits than its factorization.

205251543400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989735 (or 989726 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 31.

Adding to 205251543400 its reverse (4345152502), we get a palindrome (209596695902).

The spelling of 205251543400 in words is "two hundred five billion, two hundred fifty-one million, five hundred forty-three thousand, four hundred".