28250091 has 6 divisors (see below), whose sum is σ = 40805700. Its totient is φ = 18833388.

The previous prime is 28250087. The next prime is 28250143. The reversal of 28250091 is 19005282.

It is not a de Polignac number, because 28250091 - 2² = 28250087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28250041) 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 5 ways as a sum of consecutive naturals, for example, 1569441 + ... + 1569458.

It is an arithmetic number, because the mean of its divisors is an integer number (6800950).

Almost surely, 2^28250091 is an apocalyptic number.

28250091 is a deficient number, since it is larger than the sum of its proper divisors (12555609).

28250091 is a wasteful number, since it uses less digits than its factorization.

28250091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3138905 (or 3138902 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 28250091 is about 5315.0814669203. The cubic root of 28250091 is about 304.5602944658.

The spelling of 28250091 in words is "twenty-eight million, two hundred fifty thousand, ninety-one".