28394821 has 8 divisors (see below), whose sum is σ = 34947584. Its totient is φ = 22466160.

The previous prime is 28394819. The next prime is 28394851. The reversal of 28394821 is 12849382.

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 28394821 - 2¹ = 28394819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28394851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155925 + ... + 156106.

It is an arithmetic number, because the mean of its divisors is an integer number (4368448).

Almost surely, 2^28394821 is an apocalyptic number.

It is an amenable number.

28394821 is a deficient number, since it is larger than the sum of its proper divisors (6552763).

28394821 is a wasteful number, since it uses less digits than its factorization.

28394821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312051.

The product of its digits is 27648, while the sum is 37.

The square root of 28394821 is about 5328.6791046187. The cubic root of 28394821 is about 305.0795134445.

The spelling of 28394821 in words is "twenty-eight million, three hundred ninety-four thousand, eight hundred twenty-one".