205540245 has 24 divisors (see below), whose sum is σ = 357323616. Its totient is φ = 109297248.

The previous prime is 205540207. The next prime is 205540267. The reversal of 205540245 is 542045502.

It is not a de Polignac number, because 205540245 - 2¹³ = 205532053 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 (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9034 + ... + 22196.

It is an arithmetic number, because the mean of its divisors is an integer number (14888484).

Almost surely, 2^205540245 is an apocalyptic number.

It is an amenable number.

205540245 is a deficient number, since it is larger than the sum of its proper divisors (151783371).

205540245 is a wasteful number, since it uses less digits than its factorization.

205540245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13521 (or 13518 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 27.

The square root of 205540245 is about 14336.6748236821. The cubic root of 205540245 is about 590.1543644739.

Adding to 205540245 its reverse (542045502), we get a palindrome (747585747).

The spelling of 205540245 in words is "two hundred five million, five hundred forty thousand, two hundred forty-five".