255521261 has 4 divisors (see below), whose sum is σ = 259120224. Its totient is φ = 251922300.

The previous prime is 255521249. The next prime is 255521309. The reversal of 255521261 is 162125552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 255521261 - 2⁶ = 255521197 is a prime.

It is a super-2 number, since 2×255521261² = 130582229646060242, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255521221) 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, 1799375 + ... + 1799516.

It is an arithmetic number, because the mean of its divisors is an integer number (64780056).

Almost surely, 2^255521261 is an apocalyptic number.

It is an amenable number.

255521261 is a deficient number, since it is larger than the sum of its proper divisors (3598963).

255521261 is an equidigital number, since it uses as much as digits as its factorization.

255521261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3598962.

The product of its digits is 6000, while the sum is 29.

The square root of 255521261 is about 15985.0324053472. The cubic root of 255521261 is about 634.5643660964.

The spelling of 255521261 in words is "two hundred fifty-five million, five hundred twenty-one thousand, two hundred sixty-one".