265145261 has 4 divisors (see below), whose sum is σ = 265575612. Its totient is φ = 264714912.

The previous prime is 265145239. The next prime is 265145269. The reversal of 265145261 is 162541562.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 162541562 = 2 ⋅81270781.

It can be written as a sum of positive squares in 2 ways, for example, as 72352036 + 192793225 = 8506^2 + 13885^2 .

It is a cyclic number.

It is not a de Polignac number, because 265145261 - 2¹⁰ = 265144237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (265145269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 214250 + ... + 215483.

It is an arithmetic number, because the mean of its divisors is an integer number (66393903).

Almost surely, 2^265145261 is an apocalyptic number.

It is an amenable number.

265145261 is a deficient number, since it is larger than the sum of its proper divisors (430351).

265145261 is an equidigital number, since it uses as much as digits as its factorization.

265145261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430350.

The product of its digits is 14400, while the sum is 32.

The square root of 265145261 is about 16283.2816409961. The cubic root of 265145261 is about 642.4331702356.

The spelling of 265145261 in words is "two hundred sixty-five million, one hundred forty-five thousand, two hundred sixty-one".