28489481 has 4 divisors (see below), whose sum is σ = 28505412. Its totient is φ = 28473552.

The previous prime is 28489471. The next prime is 28489537. The reversal of 28489481 is 18498482.

It is a happy number.

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 7513081 + 20976400 = 2741^2 + 4580^2 .

It is a cyclic number.

It is not a de Polignac number, because 28489481 - 2¹⁰ = 28488457 is a prime.

It is a super-2 number, since 2×28489481² = 1623301055298722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28489411) 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, 4886 + ... + 8991.

It is an arithmetic number, because the mean of its divisors is an integer number (7126353).

Almost surely, 2^28489481 is an apocalyptic number.

It is an amenable number.

28489481 is a deficient number, since it is larger than the sum of its proper divisors (15931).

28489481 is a wasteful number, since it uses less digits than its factorization.

28489481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15930.

The product of its digits is 147456, while the sum is 44.

The square root of 28489481 is about 5337.5538404779. The cubic root of 28489481 is about 305.4181526030.

Subtracting from 28489481 its reverse (18498482), we obtain a palindrome (9990999).

The spelling of 28489481 in words is "twenty-eight million, four hundred eighty-nine thousand, four hundred eighty-one".