205673649 has 8 divisors (see below), whose sum is σ = 274323360. Its totient is φ = 137069856.

The previous prime is 205673621. The next prime is 205673653. The reversal of 205673649 is 946376502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 205673649 - 2⁵ = 205673617 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205673649.

It is not an unprimeable number, because it can be changed into a prime (205673669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 874 + ... + 20300.

It is an arithmetic number, because the mean of its divisors is an integer number (34290420).

Almost surely, 2^205673649 is an apocalyptic number.

It is an amenable number.

205673649 is a deficient number, since it is larger than the sum of its proper divisors (68649711).

205673649 is a wasteful number, since it uses less digits than its factorization.

205673649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22959.

The product of its (nonzero) digits is 272160, while the sum is 42.

The square root of 205673649 is about 14341.3266122768. The cubic root of 205673649 is about 590.2820149432.

The spelling of 205673649 in words is "two hundred five million, six hundred seventy-three thousand, six hundred forty-nine".