205431137 has 2 divisors, whose sum is σ = 205431138. Its totient is φ = 205431136.

The previous prime is 205431113. The next prime is 205431181. The reversal of 205431137 is 731134502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 158659216 + 46771921 = 12596^2 + 6839^2 .

It is a cyclic number.

It is not a de Polignac number, because 205431137 - 2⁸ = 205430881 is a prime.

It is a super-2 number, since 2×205431137² = 84403904098225538, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (205481137) 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 as a sum of consecutive naturals, namely, 102715568 + 102715569.

It is an arithmetic number, because the mean of its divisors is an integer number (102715569).

Almost surely, 2^205431137 is an apocalyptic number.

It is an amenable number.

205431137 is a deficient number, since it is larger than the sum of its proper divisors (1).

205431137 is an equidigital number, since it uses as much as digits as its factorization.

205431137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 205431137 is about 14332.8691126376. The cubic root of 205431137 is about 590.0499210848.

Adding to 205431137 its reverse (731134502), we get a palindrome (936565639).

The spelling of 205431137 in words is "two hundred five million, four hundred thirty-one thousand, one hundred thirty-seven".