205472309 has 8 divisors (see below), whose sum is σ = 242400768. Its totient is φ = 170437680.

The previous prime is 205472269. The next prime is 205472329. The reversal of 205472309 is 903274502.

It is a happy number.

205472309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 205472309 - 2⁸ = 205472053 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205472329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 473222 + ... + 473655.

It is an arithmetic number, because the mean of its divisors is an integer number (30300096).

Almost surely, 2^205472309 is an apocalyptic number.

It is an amenable number.

205472309 is a deficient number, since it is larger than the sum of its proper divisors (36928459).

205472309 is an equidigital number, since it uses as much as digits as its factorization.

205472309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 946915.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 205472309 is about 14334.3053197565. The cubic root of 205472309 is about 590.0893372332.

The spelling of 205472309 in words is "two hundred five million, four hundred seventy-two thousand, three hundred nine".