265641206033981 has 2 divisors, whose sum is σ = 265641206033982. Its totient is φ = 265641206033980.

The previous prime is 265641206033947. The next prime is 265641206033999. The reversal of 265641206033981 is 189330602146562.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208016179090756 + 57625026943225 = 14422766^2 + 7591115^2 .

It is a cyclic number.

It is not a de Polignac number, because 265641206033981 - 2²² = 265641201839677 is a prime.

It is a super-2 number, since 2×265641206033981² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (265641206333981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132820603016990 + 132820603016991.

It is an arithmetic number, because the mean of its divisors is an integer number (132820603016991).

Almost surely, 2^{265641206033981} is an apocalyptic number.

It is an amenable number.

265641206033981 is a deficient number, since it is larger than the sum of its proper divisors (1).

265641206033981 is an equidigital number, since it uses as much as digits as its factorization.

265641206033981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11197440, while the sum is 56.

The spelling of 265641206033981 in words is "two hundred sixty-five trillion, six hundred forty-one billion, two hundred six million, thirty-three thousand, nine hundred eighty-one".