28224429 has 4 divisors (see below), whose sum is σ = 37632576. Its totient is φ = 18816284.

The previous prime is 28224421. The next prime is 28224433. The reversal of 28224429 is 92442282.

It is a happy number.

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 not a de Polignac number, because 28224429 - 2³ = 28224421 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28224429.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28224421) 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, 4704069 + ... + 4704074.

It is an arithmetic number, because the mean of its divisors is an integer number (9408144).

Almost surely, 2^28224429 is an apocalyptic number.

It is an amenable number.

28224429 is a deficient number, since it is larger than the sum of its proper divisors (9408147).

28224429 is an equidigital number, since it uses as much as digits as its factorization.

28224429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9408146.

The product of its digits is 18432, while the sum is 33.

The square root of 28224429 is about 5312.6668444389. Note that the first 3 decimals coincide. The cubic root of 28224429 is about 304.4680470460.

The spelling of 28224429 in words is "twenty-eight million, two hundred twenty-four thousand, four hundred twenty-nine".