205169137931 has 2 divisors, whose sum is σ = 205169137932. Its totient is φ = 205169137930.

The previous prime is 205169137883. The next prime is 205169137949. The reversal of 205169137931 is 139731961502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 205169137931 - 2⁶ = 205169137867 is a prime.

It is a super-2 number, since 2×205169137931² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (205169137231) 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 as a sum of consecutive naturals, namely, 102584568965 + 102584568966.

It is an arithmetic number, because the mean of its divisors is an integer number (102584568966).

Almost surely, 2^205169137931 is an apocalyptic number.

205169137931 is a deficient number, since it is larger than the sum of its proper divisors (1).

205169137931 is an equidigital number, since it uses as much as digits as its factorization.

205169137931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 306180, while the sum is 47.

The spelling of 205169137931 in words is "two hundred five billion, one hundred sixty-nine million, one hundred thirty-seven thousand, nine hundred thirty-one".