205856400 has 120 divisors (see below), whose sum is σ = 698285664. Its totient is φ = 51660800.

The previous prime is 205856353. The next prime is 205856401. The reversal of 205856400 is 4658502.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (205856401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15355 + ... + 25445.

Almost surely, 2^205856400 is an apocalyptic number.

205856400 is a gapful number since it is divisible by the number (20) 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 205856400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349142832).

205856400 is an abundant number, since it is smaller than the sum of its proper divisors (492429264).

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

205856400 is a wasteful number, since it uses less digits than its factorization.

205856400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10129 (or 10118 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 205856400 is about 14347.6966792583. The cubic root of 205856400 is about 590.4567945746.

The spelling of 205856400 in words is "two hundred five million, eight hundred fifty-six thousand, four hundred".