205399994505 has 16 divisors (see below), whose sum is σ = 328702161024. Its totient is φ = 109525940480.

The previous prime is 205399994479. The next prime is 205399994531. The reversal of 205399994505 is 505499993502.

205399994505 is digitally balanced in base 2, 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 (205399994479) and next prime (205399994531).

It is not a de Polignac number, because 205399994505 - 2⁸ = 205399994249 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 1213101 + ... + 1372010.

It is an arithmetic number, because the mean of its divisors is an integer number (20543885064).

Almost surely, 2^205399994505 is an apocalyptic number.

It is an amenable number.

205399994505 is a deficient number, since it is larger than the sum of its proper divisors (123302166519).

205399994505 is a wasteful number, since it uses less digits than its factorization.

205399994505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2590416.

The product of its (nonzero) digits is 19683000, while the sum is 60.

The spelling of 205399994505 in words is "two hundred five billion, three hundred ninety-nine million, nine hundred ninety-four thousand, five hundred five".