28855881 has 24 divisors (see below), whose sum is σ = 42996096. Its totient is φ = 18637920.

The previous prime is 28855877. The next prime is 28855901. The reversal of 28855881 is 18855882.

It is not a de Polignac number, because 28855881 - 2² = 28855877 is a prime.

It is a super-2 number, since 2×28855881² = 1665323736572322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28855811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66736 + ... + 67166.

It is an arithmetic number, because the mean of its divisors is an integer number (1791504).

Almost surely, 2^28855881 is an apocalyptic number.

It is an amenable number.

28855881 is a deficient number, since it is larger than the sum of its proper divisors (14140215).

28855881 is a wasteful number, since it uses less digits than its factorization.

28855881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653 (or 650 counting only the distinct ones).

The product of its digits is 204800, while the sum is 45.

The square root of 28855881 is about 5371.7670277107. The cubic root of 28855881 is about 306.7218955088.

Subtracting from 28855881 its reverse (18855882), we obtain a palindrome (9999999).

It can be divided in two parts, 288 and 55881, that added together give a square (56169 = 237²).

The spelling of 28855881 in words is "twenty-eight million, eight hundred fifty-five thousand, eight hundred eighty-one".