28879887 has 4 divisors (see below), whose sum is σ = 38506520. Its totient is φ = 19253256.

The previous prime is 28879883. The next prime is 28879897. The reversal of 28879887 is 78897882.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 28879887 - 2² = 28879883 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28879883) 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, 4813312 + ... + 4813317.

It is an arithmetic number, because the mean of its divisors is an integer number (9626630).

Almost surely, 2^28879887 is an apocalyptic number.

28879887 is a deficient number, since it is larger than the sum of its proper divisors (9626633).

28879887 is an equidigital number, since it uses as much as digits as its factorization.

28879887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9626632.

The product of its digits is 3612672, while the sum is 57.

The square root of 28879887 is about 5374.0010234461. The cubic root of 28879887 is about 306.8069287226.

The spelling of 28879887 in words is "twenty-eight million, eight hundred seventy-nine thousand, eight hundred eighty-seven".