205981178951 has 2 divisors, whose sum is σ = 205981178952. Its totient is φ = 205981178950.

The previous prime is 205981178869. The next prime is 205981178971. The reversal of 205981178951 is 159871189502.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205981178951 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205981178971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102990589475 + 102990589476.

It is an arithmetic number, because the mean of its divisors is an integer number (102990589476).

Almost surely, 2^205981178951 is an apocalyptic number.

205981178951 is a deficient number, since it is larger than the sum of its proper divisors (1).

205981178951 is an equidigital number, since it uses as much as digits as its factorization.

205981178951 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1814400, while the sum is 56.

The spelling of 205981178951 in words is "two hundred five billion, nine hundred eighty-one million, one hundred seventy-eight thousand, nine hundred fifty-one".