205211431 has 2 divisors, whose sum is σ = 205211432. Its totient is φ = 205211430.

The previous prime is 205211423. The next prime is 205211449. The reversal of 205211431 is 134112502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205211431 - 2³ = 205211423 is a prime.

It is a super-2 number, since 2×205211431² = 84223462826135522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 205211399 and 205211408.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205211401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102605715 + 102605716.

It is an arithmetic number, because the mean of its divisors is an integer number (102605716).

Almost surely, 2^205211431 is an apocalyptic number.

205211431 is a deficient number, since it is larger than the sum of its proper divisors (1).

205211431 is an equidigital number, since it uses as much as digits as its factorization.

205211431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 205211431 is about 14325.2026512716. The cubic root of 205211431 is about 589.8394957446.

Adding to 205211431 its reverse (134112502), we get a palindrome (339323933).

It can be divided in two parts, 20521 and 1431, that added together give a cube (21952 = 28³).

The spelling of 205211431 in words is "two hundred five million, two hundred eleven thousand, four hundred thirty-one".