205240031 has 8 divisors (see below), whose sum is σ = 217461024. Its totient is φ = 193035520.

The previous prime is 205239967. The next prime is 205240037. The reversal of 205240031 is 130042502.

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

It is a cyclic number.

It is not a de Polignac number, because 205240031 - 2⁶ = 205239967 is a prime.

It is a super-2 number, since 2×205240031² = 84246940649761922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205239991 and 205240009.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205240037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29366 + ... + 35676.

It is an arithmetic number, because the mean of its divisors is an integer number (27182628).

Almost surely, 2^205240031 is an apocalyptic number.

205240031 is a deficient number, since it is larger than the sum of its proper divisors (12220993).

205240031 is a wasteful number, since it uses less digits than its factorization.

205240031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8241.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 205240031 is about 14326.2008571708. The cubic root of 205240031 is about 589.8668961447.

Adding to 205240031 its reverse (130042502), we get a palindrome (335282533).

The spelling of 205240031 in words is "two hundred five million, two hundred forty thousand, thirty-one".