265816081 has 2 divisors, whose sum is σ = 265816082. Its totient is φ = 265816080.

The previous prime is 265816073. The next prime is 265816123. The reversal of 265816081 is 180618562.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146023056 + 119793025 = 12084^2 + 10945^2 .

It is a cyclic number.

It is not a de Polignac number, because 265816081 - 2³ = 265816073 is a prime.

It is a super-2 number, since 2×265816081² = 141316377836397122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 265816081.

It is not a weakly prime, because it can be changed into another prime (265813081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132908040 + 132908041.

It is an arithmetic number, because the mean of its divisors is an integer number (132908041).

Almost surely, 2^265816081 is an apocalyptic number.

It is an amenable number.

265816081 is a deficient number, since it is larger than the sum of its proper divisors (1).

265816081 is an equidigital number, since it uses as much as digits as its factorization.

265816081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 265816081 is about 16303.8670566219. The cubic root of 265816081 is about 642.9745012854.

The spelling of 265816081 in words is "two hundred sixty-five million, eight hundred sixteen thousand, eighty-one".