205315031 has 4 divisors (see below), whose sum is σ = 208206864. Its totient is φ = 202423200.

The previous prime is 205315009. The next prime is 205315063. The reversal of 205315031 is 130513502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 205315031 - 2¹⁰ = 205314007 is a prime.

It is a super-2 number, since 2×205315031² = 84308523909061922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 205314994 and 205315012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205315531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1445810 + ... + 1445951.

It is an arithmetic number, because the mean of its divisors is an integer number (52051716).

Almost surely, 2^205315031 is an apocalyptic number.

205315031 is a deficient number, since it is larger than the sum of its proper divisors (2891833).

205315031 is an equidigital number, since it uses as much as digits as its factorization.

205315031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2891832.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 205315031 is about 14328.8181996981. The cubic root of 205315031 is about 589.9387382528.

Adding to 205315031 its reverse (130513502), we get a palindrome (335828533).

The spelling of 205315031 in words is "two hundred five million, three hundred fifteen thousand, thirty-one".