205984867349 has 4 divisors (see below), whose sum is σ = 211552025964. Its totient is φ = 200417708736.

The previous prime is 205984867271. The next prime is 205984867367. The reversal of 205984867349 is 943768489502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 104235351025 + 101749516324 = 322855^2 + 318982^2 .

It is a cyclic number.

It is not a de Polignac number, because 205984867349 - 2⁸ = 205984867093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205984867399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2783579252 + ... + 2783579325.

It is an arithmetic number, because the mean of its divisors is an integer number (52888006491).

Almost surely, 2^205984867349 is an apocalyptic number.

It is an amenable number.

205984867349 is a deficient number, since it is larger than the sum of its proper divisors (5567158615).

205984867349 is an equidigital number, since it uses as much as digits as its factorization.

205984867349 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5567158614.

The product of its (nonzero) digits is 104509440, while the sum is 65.

The spelling of 205984867349 in words is "two hundred five billion, nine hundred eighty-four million, eight hundred sixty-seven thousand, three hundred forty-nine".