255665517 has 8 divisors (see below), whose sum is σ = 340967424. Its totient is φ = 170403648.

The previous prime is 255665507. The next prime is 255665561. The reversal of 255665517 is 715566552.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 255665517 - 2⁶ = 255665453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255665507) 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 7 ways as a sum of consecutive naturals, for example, 11493 + ... + 25365.

It is an arithmetic number, because the mean of its divisors is an integer number (42620928).

Almost surely, 2^255665517 is an apocalyptic number.

It is an amenable number.

255665517 is a deficient number, since it is larger than the sum of its proper divisors (85301907).

255665517 is a wasteful number, since it uses less digits than its factorization.

255665517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20019.

The product of its digits is 315000, while the sum is 42.

The square root of 255665517 is about 15989.5439897453. The cubic root of 255665517 is about 634.6837592874.

The spelling of 255665517 in words is "two hundred fifty-five million, six hundred sixty-five thousand, five hundred seventeen".