28845921 has 16 divisors (see below), whose sum is σ = 42303744. Its totient is φ = 17372544.

The previous prime is 28845917. The next prime is 28845967. The reversal of 28845921 is 12954882.

It is not a de Polignac number, because 28845921 - 2² = 28845917 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 28845921.

It is not an unprimeable number, because it can be changed into a prime (28845121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6036 + ... + 9701.

It is an arithmetic number, because the mean of its divisors is an integer number (2643984).

Almost surely, 2^28845921 is an apocalyptic number.

It is an amenable number.

28845921 is a deficient number, since it is larger than the sum of its proper divisors (13457823).

28845921 is a wasteful number, since it uses less digits than its factorization.

28845921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15800.

The product of its digits is 46080, while the sum is 39.

The square root of 28845921 is about 5370.8398784548. The cubic root of 28845921 is about 306.6866017024.

The spelling of 28845921 in words is "twenty-eight million, eight hundred forty-five thousand, nine hundred twenty-one".