28047281 has 16 divisors (see below), whose sum is σ = 30535680. Its totient is φ = 25684560.

The previous prime is 28047269. The next prime is 28047301. The reversal of 28047281 is 18274082.

It is a de Polignac number, because none of the positive numbers 2^k-28047281 is a prime.

It is a super-2 number, since 2×28047281² = 1573299942985922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28047581) 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 in 15 ways as a sum of consecutive naturals, for example, 98966 + ... + 99248.

It is an arithmetic number, because the mean of its divisors is an integer number (1908480).

Almost surely, 2^28047281 is an apocalyptic number.

It is an amenable number.

28047281 is a deficient number, since it is larger than the sum of its proper divisors (2488399).

28047281 is a wasteful number, since it uses less digits than its factorization.

28047281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476.

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 28047281 is about 5295.9683722621. The cubic root of 28047281 is about 303.8297212663.

The spelling of 28047281 in words is "twenty-eight million, forty-seven thousand, two hundred eighty-one".