28881563 has 4 divisors (see below), whose sum is σ = 29065680. Its totient is φ = 28697448.

The previous prime is 28881551. The next prime is 28881569. The reversal of 28881563 is 36518882.

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 28881563 - 2⁶ = 28881499 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28881563.

It is not an unprimeable number, because it can be changed into a prime (28881569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91823 + ... + 92136.

It is an arithmetic number, because the mean of its divisors is an integer number (7266420).

Almost surely, 2^28881563 is an apocalyptic number.

28881563 is a deficient number, since it is larger than the sum of its proper divisors (184117).

28881563 is a wasteful number, since it uses less digits than its factorization.

28881563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184116.

The product of its digits is 92160, while the sum is 41.

The square root of 28881563 is about 5374.1569571422. The cubic root of 28881563 is about 306.8128636311.

The spelling of 28881563 in words is "twenty-eight million, eight hundred eighty-one thousand, five hundred sixty-three".