205434864 has 120 divisors (see below), whose sum is σ = 591926400. Its totient is φ = 66489984.

The previous prime is 205434847. The next prime is 205434871. The reversal of 205434864 is 468434502.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1032237 + ... + 1032435.

It is an arithmetic number, because the mean of its divisors is an integer number (4932720).

Almost surely, 2^205434864 is an apocalyptic number.

205434864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205434864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (295963200).

205434864 is an abundant number, since it is smaller than the sum of its proper divisors (386491536).

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

205434864 is a wasteful number, since it uses less digits than its factorization.

205434864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387 (or 378 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 36.

The square root of 205434864 is about 14332.9991278867. Note that the first 3 decimals coincide. The cubic root of 205434864 is about 590.0534893572.

The spelling of 205434864 in words is "two hundred five million, four hundred thirty-four thousand, eight hundred sixty-four".