28869987 has 8 divisors (see below), whose sum is σ = 40519360. Its totient is φ = 18233640.

The previous prime is 28869983. The next prime is 28869989. The reversal of 28869987 is 78996882.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28869987 - 2² = 28869983 is a prime.

It is a super-2 number, since 2×28869987² = 1666952298760338, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 506491 = 28869987 / (2 + 8 + 8 + 6 + 9 + 9 + 8 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28869983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 253189 + ... + 253302.

It is an arithmetic number, because the mean of its divisors is an integer number (5064920).

Almost surely, 2^28869987 is an apocalyptic number.

28869987 is a deficient number, since it is larger than the sum of its proper divisors (11649373).

28869987 is a wasteful number, since it uses less digits than its factorization.

28869987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506513.

The product of its digits is 3483648, while the sum is 57.

The square root of 28869987 is about 5373.0798430695. The cubic root of 28869987 is about 306.7718670003.

The spelling of 28869987 in words is "twenty-eight million, eight hundred sixty-nine thousand, nine hundred eighty-seven".