205243417728 has 256 divisors, whose sum is σ = 627691680000. Its totient is φ = 65944682496.

The previous prime is 205243417721. The next prime is 205243417807. The reversal of 205243417728 is 827714342502.

205243417728 is a `hidden beast` number, since 2 + 0 + 524 + 34 + 1 + 77 + 28 = 666.

It is not an unprimeable number, because it can be changed into a prime (205243417721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 77070925 + ... + 77073587.

It is an arithmetic number, because the mean of its divisors is an integer number (2451920625).

Almost surely, 2^205243417728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205243417728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313845840000).

205243417728 is an abundant number, since it is smaller than the sum of its proper divisors (422448262272).

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

205243417728 is a wasteful number, since it uses less digits than its factorization.

205243417728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3484 (or 3466 counting only the distinct ones).

The product of its (nonzero) digits is 752640, while the sum is 45.

The spelling of 205243417728 in words is "two hundred five billion, two hundred forty-three million, four hundred seventeen thousand, seven hundred twenty-eight".