28798921 has 8 divisors (see below), whose sum is σ = 30691584. Its totient is φ = 26959680.

The previous prime is 28798883. The next prime is 28798937. The reversal of 28798921 is 12989782.

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

It is not a de Polignac number, because 28798921 - 2⁷ = 28798793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28796921) 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, 12240 + ... + 14401.

It is an arithmetic number, because the mean of its divisors is an integer number (3836448).

Almost surely, 2^28798921 is an apocalyptic number.

It is an amenable number.

28798921 is a deficient number, since it is larger than the sum of its proper divisors (1892663).

28798921 is a wasteful number, since it uses less digits than its factorization.

28798921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26711.

The product of its digits is 145152, while the sum is 46.

The square root of 28798921 is about 5366.4626151684. The cubic root of 28798921 is about 306.5199449102.

The spelling of 28798921 in words is "twenty-eight million, seven hundred ninety-eight thousand, nine hundred twenty-one".