205423251 has 16 divisors (see below), whose sum is σ = 299946240. Its totient is φ = 124020320.

The previous prime is 205423249. The next prime is 205423259. The reversal of 205423251 is 152324502.

It is a cyclic number.

It is not a de Polignac number, because 205423251 - 2¹ = 205423249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (205423259) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 3156 + ... + 20513.

It is an arithmetic number, because the mean of its divisors is an integer number (18746640).

Almost surely, 2^205423251 is an apocalyptic number.

205423251 is a deficient number, since it is larger than the sum of its proper divisors (94522989).

205423251 is a wasteful number, since it uses less digits than its factorization.

205423251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23946.

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 205423251 is about 14332.5940080643. The cubic root of 205423251 is about 590.0423707960.

Adding to 205423251 its reverse (152324502), we get a palindrome (357747753).

The spelling of 205423251 in words is "two hundred five million, four hundred twenty-three thousand, two hundred fifty-one".