255591891 has 24 divisors (see below), whose sum is σ = 379529280. Its totient is φ = 165686400.

The previous prime is 255591887. The next prime is 255591979. The reversal of 255591891 is 198195552.

255591891 is a `hidden beast` number, since 2 + 5 + 559 + 1 + 8 + 91 = 666.

It is not a de Polignac number, because 255591891 - 2² = 255591887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (255591841) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46246 + ... + 51476.

It is an arithmetic number, because the mean of its divisors is an integer number (15813720).

Almost surely, 2^255591891 is an apocalyptic number.

255591891 is a deficient number, since it is larger than the sum of its proper divisors (123937389).

255591891 is a wasteful number, since it uses less digits than its factorization.

255591891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5387 (or 5384 counting only the distinct ones).

The product of its digits is 162000, while the sum is 45.

The square root of 255591891 is about 15987.2415069017. The cubic root of 255591891 is about 634.6228284882.

The spelling of 255591891 in words is "two hundred fifty-five million, five hundred ninety-one thousand, eight hundred ninety-one".