28961664 has 64 divisors (see below), whose sum is σ = 77520000. Its totient is φ = 9580032.

The previous prime is 28961617. The next prime is 28961683. The reversal of 28961664 is 46616982.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 76227 + ... + 76605.

It is an arithmetic number, because the mean of its divisors is an integer number (1211250).

Almost surely, 2^28961664 is an apocalyptic number.

28961664 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 28961664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38760000).

28961664 is an abundant number, since it is smaller than the sum of its proper divisors (48558336).

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

28961664 is a wasteful number, since it uses less digits than its factorization.

28961664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595 (or 583 counting only the distinct ones).

The product of its digits is 124416, while the sum is 42.

The square root of 28961664 is about 5381.6042217911. The cubic root of 28961664 is about 307.0962431719.

It can be divided in two parts, 2896 and 1664, that added together give a triangular number (4560 = T₉₅).

The spelling of 28961664 in words is "twenty-eight million, nine hundred sixty-one thousand, six hundred sixty-four".