255135021 has 32 divisors (see below), whose sum is σ = 379054080. Its totient is φ = 151905600.

The previous prime is 255135019. The next prime is 255135029. The reversal of 255135021 is 120531552.

It is a happy number.

It is not a de Polignac number, because 255135021 - 2¹ = 255135019 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 255134982 and 255135000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255135029) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91711 + ... + 94451.

It is an arithmetic number, because the mean of its divisors is an integer number (11845440).

Almost surely, 2^255135021 is an apocalyptic number.

It is an amenable number.

255135021 is a deficient number, since it is larger than the sum of its proper divisors (123919059).

255135021 is a wasteful number, since it uses less digits than its factorization.

255135021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2857.

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 255135021 is about 15972.9465346880. The cubic root of 255135021 is about 634.2444739454.

Adding to 255135021 its reverse (120531552), we get a palindrome (375666573).

The spelling of 255135021 in words is "two hundred fifty-five million, one hundred thirty-five thousand, twenty-one".