255372021 has 20 divisors (see below), whose sum is σ = 381912300. Its totient is φ = 170055936.

The previous prime is 255371983. The next prime is 255372023. The reversal of 255372021 is 120273552.

It can be written as a sum of positive squares in 2 ways, for example, as 129618225 + 125753796 = 11385^2 + 11214^2 .

It is a de Polignac number, because none of the positive numbers 2^k-255372021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255372023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 134245 + ... + 136133.

It is an arithmetic number, because the mean of its divisors is an integer number (19095615).

Almost surely, 2^255372021 is an apocalyptic number.

It is an amenable number.

255372021 is a deficient number, since it is larger than the sum of its proper divisors (126540279).

255372021 is a wasteful number, since it uses less digits than its factorization.

255372021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3570 (or 3561 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The square root of 255372021 is about 15980.3636066267. The cubic root of 255372021 is about 634.4408006066.

The spelling of 255372021 in words is "two hundred fifty-five million, three hundred seventy-two thousand, twenty-one".