28431839 has 2 divisors, whose sum is σ = 28431840. Its totient is φ = 28431838.

The previous prime is 28431833. The next prime is 28431853. The reversal of 28431839 is 93813482.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28431839 - 2²⁰ = 27383263 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28431833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14215919 + 14215920.

It is an arithmetic number, because the mean of its divisors is an integer number (14215920).

Almost surely, 2^28431839 is an apocalyptic number.

28431839 is a deficient number, since it is larger than the sum of its proper divisors (1).

28431839 is an equidigital number, since it uses as much as digits as its factorization.

28431839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 38.

The square root of 28431839 is about 5332.1514419604. The cubic root of 28431839 is about 305.2120320855.

It can be divided in two parts, 284 and 31839, that added together give a palindrome (32123).

The spelling of 28431839 in words is "twenty-eight million, four hundred thirty-one thousand, eight hundred thirty-nine".