28872864 has 72 divisors (see below), whose sum is σ = 84963060. Its totient is φ = 9289728.

The previous prime is 28872847. The next prime is 28872869. The reversal of 28872864 is 46827882.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 26010000 + 2862864 = 5100^2 + 1692^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is not an unprimeable number, because it can be changed into a prime (28872869) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6624 + ... + 10080.

Almost surely, 2^28872864 is an apocalyptic number.

28872864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28872864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42481530).

28872864 is an abundant number, since it is smaller than the sum of its proper divisors (56090196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28872864 is a wasteful number, since it uses less digits than its factorization.

28872864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3502 (or 3491 counting only the distinct ones).

The product of its digits is 344064, while the sum is 45.

The square root of 28872864 is about 5373.3475599481. The cubic root of 28872864 is about 306.7820569754.

The spelling of 28872864 in words is "twenty-eight million, eight hundred seventy-two thousand, eight hundred sixty-four".