205215856 has 10 divisors (see below), whose sum is σ = 397605752. Its totient is φ = 102607920.

The previous prime is 205215833. The next prime is 205215869. The reversal of 205215856 is 658512502.

It is a super-2 number, since 2×205215856² = 84227095107625472, which contains 22 as substring.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 6412980 + ... + 6413011.

Almost surely, 2^205215856 is an apocalyptic number.

It is an amenable number.

205215856 is a deficient number, since it is larger than the sum of its proper divisors (192389896).

205215856 is a wasteful number, since it uses less digits than its factorization.

205215856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12825999 (or 12825993 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 34.

The square root of 205215856 is about 14325.3570985159. The cubic root of 205215856 is about 589.8437353086.

The spelling of 205215856 in words is "two hundred five million, two hundred fifteen thousand, eight hundred fifty-six".