28343939 has 4 divisors (see below), whose sum is σ = 30524256. Its totient is φ = 26163624.

The previous prime is 28343911. The next prime is 28343977. The reversal of 28343939 is 93934382.

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

It is a cyclic number.

It is not a de Polignac number, because 28343939 - 2⁸ = 28343683 is a prime.

It is a Duffinian number.

28343939 is a modest number, since divided by 3939 gives 2834 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 28343896 and 28343905.

It is not an unprimeable number, because it can be changed into a prime (28343989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1090139 + ... + 1090164.

It is an arithmetic number, because the mean of its divisors is an integer number (7631064).

Almost surely, 2^28343939 is an apocalyptic number.

28343939 is a deficient number, since it is larger than the sum of its proper divisors (2180317).

28343939 is a wasteful number, since it uses less digits than its factorization.

28343939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180316.

The product of its digits is 139968, while the sum is 41.

The square root of 28343939 is about 5323.9026099282. The cubic root of 28343939 is about 304.8971757662.

The spelling of 28343939 in words is "twenty-eight million, three hundred forty-three thousand, nine hundred thirty-nine".