28843381 has 4 divisors (see below), whose sum is σ = 32963872. Its totient is φ = 24722892.

The previous prime is 28843379. The next prime is 28843391. The reversal of 28843381 is 18334882.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18334882 = 2 ⋅9167441.

It is a cyclic number.

It is not a de Polignac number, because 28843381 - 2¹ = 28843379 is a prime.

It is a super-2 number, since 2×28843381² = 1663881255022322, which contains 22 as substring.

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 28843381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28843391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2060235 + ... + 2060248.

It is an arithmetic number, because the mean of its divisors is an integer number (8240968).

Almost surely, 2^28843381 is an apocalyptic number.

It is an amenable number.

28843381 is a deficient number, since it is larger than the sum of its proper divisors (4120491).

28843381 is an equidigital number, since it uses as much as digits as its factorization.

28843381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4120490.

The product of its digits is 36864, while the sum is 37.

The square root of 28843381 is about 5370.6034111634. The cubic root of 28843381 is about 306.6775997730.

The spelling of 28843381 in words is "twenty-eight million, eight hundred forty-three thousand, three hundred eighty-one".