205215912 has 192 divisors, whose sum is σ = 640224000. Its totient is φ = 58821120.

The previous prime is 205215911. The next prime is 205215917. The reversal of 205215912 is 219512502.

205215912 is a `hidden beast` number, since 20 + 52 + 1 + 591 + 2 = 666.

It is a super-2 number, since 2×205215912² = 84227141075983488, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (205215911) by changing a digit.

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, 1377214 + ... + 1377362.

It is an arithmetic number, because the mean of its divisors is an integer number (3334500).

Almost surely, 2^205215912 is an apocalyptic number.

205215912 is a gapful number since it is divisible by the number (22) 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 205215912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (320112000).

205215912 is an abundant number, since it is smaller than the sum of its proper divisors (435008088).

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

205215912 is a wasteful number, since it uses less digits than its factorization.

205215912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 205215912 is about 14325.3590530918. The cubic root of 205215912 is about 589.8437889615.

The spelling of 205215912 in words is "two hundred five million, two hundred fifteen thousand, nine hundred twelve".