205447680 has 240 divisors, whose sum is σ = 733785624. Its totient is φ = 53084160.

The previous prime is 205447651. The next prime is 205447709. The reversal of 205447680 is 86744502.

205447680 is a `hidden beast` number, since 205 + 447 + 6 + 8 + 0 = 666.

205447680 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (205447651) and next prime (205447709).

It can be written as a sum of positive squares in 4 ways, for example, as 203233536 + 2214144 = 14256^2 + 1488^2 .

It is a tau number, because it is divible by the number of its divisors (240).

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

It is an unprimeable number.

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, 852360 + ... + 852600.

Almost surely, 2^205447680 is an apocalyptic number.

205447680 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 205447680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366892812).

205447680 is an abundant number, since it is smaller than the sum of its proper divisors (528337944).

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

205447680 is a wasteful number, since it uses less digits than its factorization.

205447680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 288 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 205447680 is about 14333.4462011060. The cubic root of 205447680 is about 590.0657592126.

It can be divided in two parts, 20544 and 7680, that added together give a square (28224 = 168²).

The spelling of 205447680 in words is "two hundred five million, four hundred forty-seven thousand, six hundred eighty".