28540191 has 8 divisors (see below), whose sum is σ = 38621824. Its totient is φ = 18742680.

The previous prime is 28540189. The next prime is 28540201. The reversal of 28540191 is 19104582.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28540191 - 2¹ = 28540189 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 (28540121) 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 7 ways as a sum of consecutive naturals, for example, 70795 + ... + 71196.

It is an arithmetic number, because the mean of its divisors is an integer number (4827728).

Almost surely, 2^28540191 is an apocalyptic number.

28540191 is a deficient number, since it is larger than the sum of its proper divisors (10081633).

28540191 is a wasteful number, since it uses less digits than its factorization.

28540191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142061.

The product of its (nonzero) digits is 2880, while the sum is 30.

The square root of 28540191 is about 5342.3020318960. The cubic root of 28540191 is about 305.5992554040.

The spelling of 28540191 in words is "twenty-eight million, five hundred forty thousand, one hundred ninety-one".