28889664 has 112 divisors (see below), whose sum is σ = 82954368. Its totient is φ = 8839168.

The previous prime is 28889639. The next prime is 28889683. The reversal of 28889664 is 46698882.

It is a happy number.

It is a super-2 number, since 2×28889664² = 1669225372065792, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 172909 + ... + 173075.

It is an arithmetic number, because the mean of its divisors is an integer number (740664).

Almost surely, 2^28889664 is an apocalyptic number.

28889664 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 28889664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41477184).

28889664 is an abundant number, since it is smaller than the sum of its proper divisors (54064704).

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

28889664 is a wasteful number, since it uses less digits than its factorization.

28889664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252 (or 242 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 51.

The square root of 28889664 is about 5374.9106039078. The cubic root of 28889664 is about 306.8415469664.

The spelling of 28889664 in words is "twenty-eight million, eight hundred eighty-nine thousand, six hundred sixty-four".