205106220 has 144 divisors (see below), whose sum is σ = 688746240. Its totient is φ = 48988800.

The previous prime is 205106219. The next prime is 205106333. The reversal of 205106220 is 22601502.

It is a super-2 number, since 2×205106220² = 84137122965376800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 205106193 and 205106202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 139851 + ... + 141309.

It is an arithmetic number, because the mean of its divisors is an integer number (4782960).

Almost surely, 2^205106220 is an apocalyptic number.

205106220 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 205106220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (344373120).

205106220 is an abundant number, since it is smaller than the sum of its proper divisors (483640020).

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

205106220 is a wasteful number, since it uses less digits than its factorization.

205106220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1556 (or 1551 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 205106220 is about 14321.5299462034. The cubic root of 205106220 is about 589.7386758058.

Adding to 205106220 its reverse (22601502), we get a palindrome (227707722).

The spelling of 205106220 in words is "two hundred five million, one hundred six thousand, two hundred twenty".