205705720215 has 24 divisors (see below), whose sum is σ = 361578511008. Its totient is φ = 108164508480.

The previous prime is 205705720201. The next prime is 205705720223. The reversal of 205705720215 is 512027507502.

205705720215 is a `hidden beast` number, since 2 + 0 + 5 + 70 + 572 + 0 + 2 + 15 = 666.

205705720215 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 205705720215 - 2¹² = 205705716119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205705720215.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32188624 + ... + 32195013.

It is an arithmetic number, because the mean of its divisors is an integer number (15065771292).

Almost surely, 2^205705720215 is an apocalyptic number.

205705720215 is a deficient number, since it is larger than the sum of its proper divisors (155872790793).

205705720215 is a wasteful number, since it uses less digits than its factorization.

205705720215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64383719 (or 64383716 counting only the distinct ones).

The product of its (nonzero) digits is 49000, while the sum is 36.

The spelling of 205705720215 in words is "two hundred five billion, seven hundred five million, seven hundred twenty thousand, two hundred fifteen".