28501091 has 8 divisors (see below), whose sum is σ = 29053200. Its totient is φ = 27951840.

The previous prime is 28501087. The next prime is 28501103. The reversal of 28501091 is 19010582.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28501091 - 2² = 28501087 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28501091.

It is not an unprimeable number, because it can be changed into a prime (28501001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39845 + ... + 40553.

It is an arithmetic number, because the mean of its divisors is an integer number (3631650).

Almost surely, 2^28501091 is an apocalyptic number.

28501091 is a deficient number, since it is larger than the sum of its proper divisors (552109).

28501091 is an equidigital number, since it uses as much as digits as its factorization.

28501091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1429.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 28501091 is about 5338.6413065498. The cubic root of 28501091 is about 305.4596348514.

The spelling of 28501091 in words is "twenty-eight million, five hundred one thousand, ninety-one".