255183991 has 4 divisors (see below), whose sum is σ = 270194832. Its totient is φ = 240173152.

The previous prime is 255183977. The next prime is 255183997. The reversal of 255183991 is 199381552.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 255183991 - 2¹¹ = 255181943 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 (255183997) 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, 7505395 + ... + 7505428.

It is an arithmetic number, because the mean of its divisors is an integer number (67548708).

Almost surely, 2^255183991 is an apocalyptic number.

255183991 is a deficient number, since it is larger than the sum of its proper divisors (15010841).

255183991 is a wasteful number, since it uses less digits than its factorization.

255183991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15010840.

The product of its digits is 97200, while the sum is 43.

The square root of 255183991 is about 15974.4793655380. The cubic root of 255183991 is about 634.2850498006.

The spelling of 255183991 in words is "two hundred fifty-five million, one hundred eighty-three thousand, nine hundred ninety-one".