28887861 has 16 divisors (see below), whose sum is σ = 39980864. Its totient is φ = 18537984.

The previous prime is 28887853. The next prime is 28887863. The reversal of 28887861 is 16878882.

It is not a de Polignac number, because 28887861 - 2³ = 28887853 is a prime.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 28887861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28887863) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9426 + ... + 12108.

It is an arithmetic number, because the mean of its divisors is an integer number (2498804).

Almost surely, 2^28887861 is an apocalyptic number.

It is an amenable number.

28887861 is a deficient number, since it is larger than the sum of its proper divisors (11093003).

28887861 is a wasteful number, since it uses less digits than its factorization.

28887861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2820.

The product of its digits is 344064, while the sum is 48.

The square root of 28887861 is about 5374.7428775710. The cubic root of 28887861 is about 306.8351635205.

The spelling of 28887861 in words is "twenty-eight million, eight hundred eighty-seven thousand, eight hundred sixty-one".