255827021 has 2 divisors, whose sum is σ = 255827022. Its totient is φ = 255827020.

The previous prime is 255826993. The next prime is 255827023. The reversal of 255827021 is 120728552.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 229674025 + 26152996 = 15155^2 + 5114^2 .

It is a cyclic number.

It is not a de Polignac number, because 255827021 - 2²⁶ = 188718157 is a prime.

It is a Sophie Germain prime.

Together with 255827023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (255827023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127913510 + 127913511.

It is an arithmetic number, because the mean of its divisors is an integer number (127913511).

Almost surely, 2^255827021 is an apocalyptic number.

It is an amenable number.

255827021 is a deficient number, since it is larger than the sum of its proper divisors (1).

255827021 is an equidigital number, since it uses as much as digits as its factorization.

255827021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11200, while the sum is 32.

The square root of 255827021 is about 15994.5934928025. The cubic root of 255827021 is about 634.8173744769.

The spelling of 255827021 in words is "two hundred fifty-five million, eight hundred twenty-seven thousand, twenty-one".