265634491 has 2 divisors, whose sum is σ = 265634492. Its totient is φ = 265634490.

The previous prime is 265634489. The next prime is 265634533. The reversal of 265634491 is 194436562.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 265634491 - 2¹ = 265634489 is a prime.

Together with 265634489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (265634191) 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, 132817245 + 132817246.

It is an arithmetic number, because the mean of its divisors is an integer number (132817246).

Almost surely, 2^265634491 is an apocalyptic number.

265634491 is a deficient number, since it is larger than the sum of its proper divisors (1).

265634491 is an equidigital number, since it uses as much as digits as its factorization.

265634491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 155520, while the sum is 40.

The square root of 265634491 is about 16298.2971809941. The cubic root of 265634491 is about 642.8280537408.

The spelling of 265634491 in words is "two hundred sixty-five million, six hundred thirty-four thousand, four hundred ninety-one".