28223969 has 4 divisors (see below), whose sum is σ = 28244160. Its totient is φ = 28203780.

The previous prime is 28223941. The next prime is 28224011. The reversal of 28223969 is 96932282.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28223969 is a prime.

It is a super-2 number, since 2×28223969² = 1593184852225922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28223929) 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, 7829 + ... + 10850.

It is an arithmetic number, because the mean of its divisors is an integer number (7061040).

Almost surely, 2^28223969 is an apocalyptic number.

It is an amenable number.

28223969 is a deficient number, since it is larger than the sum of its proper divisors (20191).

28223969 is a wasteful number, since it uses less digits than its factorization.

28223969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20190.

The product of its digits is 93312, while the sum is 41.

The square root of 28223969 is about 5312.6235515045. The cubic root of 28223969 is about 304.4663929699.

It can be divided in two parts, 28223 and 969, that added together give a palindrome (29192).

The spelling of 28223969 in words is "twenty-eight million, two hundred twenty-three thousand, nine hundred sixty-nine".