28561824 has 36 divisors (see below), whose sum is σ = 81223506. Its totient is φ = 9520512.

The previous prime is 28561823. The next prime is 28561829. The reversal of 28561824 is 42816582.

It can be written as a sum of positive squares in only one way, i.e., 27751824 + 810000 = 5268^2 + 900^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (28561823) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 49299 + ... + 49874.

Almost surely, 2^28561824 is an apocalyptic number.

28561824 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28561824 is an abundant number, since it is smaller than the sum of its proper divisors (52661682).

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

28561824 is a wasteful number, since it uses less digits than its factorization.

28561824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99189 (or 99178 counting only the distinct ones).

The product of its digits is 30720, while the sum is 36.

The square root of 28561824 is about 5344.3263373413. The cubic root of 28561824 is about 305.6764489897.

The spelling of 28561824 in words is "twenty-eight million, five hundred sixty-one thousand, eight hundred twenty-four".