28145891 has 8 divisors (see below), whose sum is σ = 29030400. Its totient is φ = 27275080.

The previous prime is 28145879. The next prime is 28145893. The reversal of 28145891 is 19854182.

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 28145891 - 2¹⁰ = 28144867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28145893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 830 + ... + 7548.

It is an arithmetic number, because the mean of its divisors is an integer number (3628800).

Almost surely, 2^28145891 is an apocalyptic number.

28145891 is a deficient number, since it is larger than the sum of its proper divisors (884509).

28145891 is an equidigital number, since it uses as much as digits as its factorization.

28145891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6849.

The product of its digits is 23040, while the sum is 38.

The square root of 28145891 is about 5305.2701156492. The cubic root of 28145891 is about 304.1853779027.

The spelling of 28145891 in words is "twenty-eight million, one hundred forty-five thousand, eight hundred ninety-one".