28091263 has 4 divisors (see below), whose sum is σ = 28113760. Its totient is φ = 28068768.

The previous prime is 28091249. The next prime is 28091279. The reversal of 28091263 is 36219082.

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 28091263 - 2¹³ = 28083071 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 (28091213) 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, 9258 + ... + 11911.

It is an arithmetic number, because the mean of its divisors is an integer number (7028440).

Almost surely, 2^28091263 is an apocalyptic number.

28091263 is a deficient number, since it is larger than the sum of its proper divisors (22497).

28091263 is a wasteful number, since it uses less digits than its factorization.

28091263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22496.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 28091263 is about 5300.1191496041. The cubic root of 28091263 is about 303.9884539417.

The spelling of 28091263 in words is "twenty-eight million, ninety-one thousand, two hundred sixty-three".