265605191 has 2 divisors, whose sum is σ = 265605192. Its totient is φ = 265605190.

The previous prime is 265605181. The next prime is 265605233. The reversal of 265605191 is 191506562.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 265605191 - 2¹⁸ = 265343047 is a prime.

It is a super-2 number, since 2×265605191² = 141092234972292962, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (265605121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132802595 + 132802596.

It is an arithmetic number, because the mean of its divisors is an integer number (132802596).

Almost surely, 2^265605191 is an apocalyptic number.

265605191 is a deficient number, since it is larger than the sum of its proper divisors (1).

265605191 is an equidigital number, since it uses as much as digits as its factorization.

265605191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 265605191 is about 16297.3982892976. The cubic root of 265605191 is about 642.8044178110.

The spelling of 265605191 in words is "two hundred sixty-five million, six hundred five thousand, one hundred ninety-one".