28431443 has 4 divisors (see below), whose sum is σ = 28506840. Its totient is φ = 28356048.

The previous prime is 28431439. The next prime is 28431457. The reversal of 28431443 is 34413482.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34413482 = 2 ⋅17206741.

It is a cyclic number.

It is not a de Polignac number, because 28431443 - 2² = 28431439 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28431943) 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, 37130 + ... + 37887.

It is an arithmetic number, because the mean of its divisors is an integer number (7126710).

Almost surely, 2^28431443 is an apocalyptic number.

28431443 is a deficient number, since it is larger than the sum of its proper divisors (75397).

28431443 is an equidigital number, since it uses as much as digits as its factorization.

28431443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75396.

The product of its digits is 9216, while the sum is 29.

The square root of 28431443 is about 5332.1143086022. The cubic root of 28431443 is about 305.2106150764.

The spelling of 28431443 in words is "twenty-eight million, four hundred thirty-one thousand, four hundred forty-three".