28043109 has 12 divisors (see below), whose sum is σ = 40578252. Its totient is φ = 18662400.

The previous prime is 28043053. The next prime is 28043117. The reversal of 28043109 is 90134082.

It can be written as a sum of positive squares in 2 ways, for example, as 25553025 + 2490084 = 5055^2 + 1578^2 .

It is not a de Polignac number, because 28043109 - 2¹² = 28039013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28043129) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3339 + ... + 8199.

It is an arithmetic number, because the mean of its divisors is an integer number (3381521).

Almost surely, 2^28043109 is an apocalyptic number.

It is an amenable number.

28043109 is a deficient number, since it is larger than the sum of its proper divisors (12535143).

28043109 is a wasteful number, since it uses less digits than its factorization.

28043109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5508 (or 5505 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 28043109 is about 5295.5744730860. The cubic root of 28043109 is about 303.8146557483.

The spelling of 28043109 in words is "twenty-eight million, forty-three thousand, one hundred nine".