265056561 has 48 divisors (see below), whose sum is σ = 484144128. Its totient is φ = 135727200.

The previous prime is 265056557. The next prime is 265056569. The reversal of 265056561 is 165650562.

It is a happy number.

It is not a de Polignac number, because 265056561 - 2² = 265056557 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (265056569) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 46510 + ... + 51896.

It is an arithmetic number, because the mean of its divisors is an integer number (10086336).

Almost surely, 2^265056561 is an apocalyptic number.

265056561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

265056561 is a deficient number, since it is larger than the sum of its proper divisors (219087567).

265056561 is a wasteful number, since it uses less digits than its factorization.

265056561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5482 (or 5479 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 36.

The square root of 265056561 is about 16280.5577607157. The cubic root of 265056561 is about 642.3615237508.

The spelling of 265056561 in words is "two hundred sixty-five million, fifty-six thousand, five hundred sixty-one".