28444429 has 4 divisors (see below), whose sum is σ = 30632476. Its totient is φ = 26256384.

The previous prime is 28444421. The next prime is 28444433. The reversal of 28444429 is 92444482.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3143529 + 25300900 = 1773^2 + 5030^2 .

It is a cyclic number.

It is not a de Polignac number, because 28444429 - 2³ = 28444421 is a prime.

It is a super-2 number, since 2×28444429² = 1618171082272082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28444421) 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 3 ways as a sum of consecutive naturals, for example, 1094004 + ... + 1094029.

It is an arithmetic number, because the mean of its divisors is an integer number (7658119).

Almost surely, 2^28444429 is an apocalyptic number.

It is an amenable number.

28444429 is a deficient number, since it is larger than the sum of its proper divisors (2188047).

28444429 is a wasteful number, since it uses less digits than its factorization.

28444429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2188046.

The product of its digits is 73728, while the sum is 37.

The square root of 28444429 is about 5333.3318854165. The cubic root of 28444429 is about 305.2570760992.

The spelling of 28444429 in words is "twenty-eight million, four hundred forty-four thousand, four hundred twenty-nine".