255387999 has 4 divisors (see below), whose sum is σ = 340517336. Its totient is φ = 170258664.

The previous prime is 255387997. The next prime is 255388009. The reversal of 255387999 is 999783552.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 255387999 - 2¹ = 255387997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255387997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42564664 + ... + 42564669.

It is an arithmetic number, because the mean of its divisors is an integer number (85129334).

Almost surely, 2^255387999 is an apocalyptic number.

255387999 is a deficient number, since it is larger than the sum of its proper divisors (85129337).

255387999 is an equidigital number, since it uses as much as digits as its factorization.

255387999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85129336.

The product of its digits is 6123600, while the sum is 57.

The square root of 255387999 is about 15980.8635248537. The cubic root of 255387999 is about 634.4540321314.

The spelling of 255387999 in words is "two hundred fifty-five million, three hundred eighty-seven thousand, nine hundred ninety-nine".