255021 has 12 divisors (see below), whose sum is σ = 368928. Its totient is φ = 156624.

The previous prime is 255019. The next prime is 255023. The reversal of 255021 is 120552.

It is an interprime number because it is at equal distance from previous prime (255019) and next prime (255023).

It is not a de Polignac number, because 255021 - 2¹ = 255019 is a prime.

It is a hoax number, since the sum of its digits (15) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255023) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 256 + ... + 758.

It is an arithmetic number, because the mean of its divisors is an integer number (30744).

2²⁵⁵⁰²¹ is an apocalyptic number.

It is an amenable number.

255021 is a deficient number, since it is larger than the sum of its proper divisors (113907).

255021 is a wasteful number, since it uses less digits than its factorization.

255021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532 (or 519 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 15.

The square root of 255021 is about 504.9960395884. The cubic root of 255021 is about 63.4149977621.

Adding to 255021 its reverse (120552), we get a palindrome (375573).

The spelling of 255021 in words is "two hundred fifty-five thousand, twenty-one".