265748521 has 4 divisors (see below), whose sum is σ = 266325444. Its totient is φ = 265171600.

The previous prime is 265748491. The next prime is 265748533. The reversal of 265748521 is 125847562.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 125847562 = 2 ⋅62923781.

It can be written as a sum of positive squares in 2 ways, for example, as 116640000 + 149108521 = 10800^2 + 12211^2 .

It is a cyclic number.

It is not a de Polignac number, because 265748521 - 2⁹ = 265748009 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (265728521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 287770 + ... + 288691.

It is an arithmetic number, because the mean of its divisors is an integer number (66581361).

Almost surely, 2^265748521 is an apocalyptic number.

It is an amenable number.

265748521 is a deficient number, since it is larger than the sum of its proper divisors (576923).

265748521 is an equidigital number, since it uses as much as digits as its factorization.

265748521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576922.

The product of its digits is 134400, while the sum is 40.

The square root of 265748521 is about 16301.7950238616. The cubic root of 265748521 is about 642.9200237210.

The spelling of 265748521 in words is "two hundred sixty-five million, seven hundred forty-eight thousand, five hundred twenty-one".