205312831 has 8 divisors (see below), whose sum is σ = 214053840. Its totient is φ = 196752192.

The previous prime is 205312829. The next prime is 205312853. The reversal of 205312831 is 138213502.

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 205312831 - 2¹ = 205312829 is a prime.

It is a super-2 number, since 2×205312831² = 84306717146469122, 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 = 205312796 and 205312805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205312631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42766 + ... + 47323.

It is an arithmetic number, because the mean of its divisors is an integer number (26756730).

Almost surely, 2^205312831 is an apocalyptic number.

205312831 is a deficient number, since it is larger than the sum of its proper divisors (8741009).

205312831 is an equidigital number, since it uses as much as digits as its factorization.

205312831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90185.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 205312831 is about 14328.7414311237. The cubic root of 205312831 is about 589.9366311334.

It can be divided in two parts, 2053 and 12831, that added together give a square (14884 = 122²).

The spelling of 205312831 in words is "two hundred five million, three hundred twelve thousand, eight hundred thirty-one".