205316645 has 4 divisors (see below), whose sum is σ = 246379980. Its totient is φ = 164253312.

The previous prime is 205316623. The next prime is 205316669. The reversal of 205316645 is 546613502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 546613502 = 2 ⋅273306751.

It can be written as a sum of positive squares in 2 ways, for example, as 69989956 + 135326689 = 8366^2 + 11633^2 .

It is a cyclic number.

It is not a de Polignac number, because 205316645 - 2⁶ = 205316581 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20531660 + ... + 20531669.

It is an arithmetic number, because the mean of its divisors is an integer number (61594995).

Almost surely, 2^205316645 is an apocalyptic number.

It is an amenable number.

205316645 is a deficient number, since it is larger than the sum of its proper divisors (41063335).

205316645 is an equidigital number, since it uses as much as digits as its factorization.

205316645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41063334.

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 205316645 is about 14328.8745196544. The cubic root of 205316645 is about 589.9402841027.

The spelling of 205316645 in words is "two hundred five million, three hundred sixteen thousand, six hundred forty-five".