205542243 has 6 divisors (see below), whose sum is σ = 296894364. Its totient is φ = 137028156.

The previous prime is 205542241. The next prime is 205542263. The reversal of 205542243 is 342245502.

It is a happy number.

It is not a de Polignac number, because 205542243 - 2¹ = 205542241 is a prime.

It is a super-2 number, since 2×205542243² = 84495227314942098, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (205542241) 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 5 ways as a sum of consecutive naturals, for example, 11419005 + ... + 11419022.

It is an arithmetic number, because the mean of its divisors is an integer number (49482394).

Almost surely, 2^205542243 is an apocalyptic number.

205542243 is a deficient number, since it is larger than the sum of its proper divisors (91352121).

205542243 is a wasteful number, since it uses less digits than its factorization.

205542243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22838033 (or 22838030 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 27.

The square root of 205542243 is about 14336.7445049425. The cubic root of 205542243 is about 590.1562767103.

Adding to 205542243 its reverse (342245502), we get a palindrome (547787745).

The spelling of 205542243 in words is "two hundred five million, five hundred forty-two thousand, two hundred forty-three".