28664540 has 48 divisors (see below), whose sum is σ = 63829920. Its totient is φ = 10782720.

The previous prime is 28664539. The next prime is 28664549. The reversal of 28664540 is 4546682.

It is a self number, because there is not a number n which added to its sum of digits gives 28664540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28664549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 91424 + ... + 91736.

It is an arithmetic number, because the mean of its divisors is an integer number (1329790).

Almost surely, 2^28664540 is an apocalyptic number.

28664540 is a gapful number since it is divisible by the number (20) 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 28664540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31914960).

28664540 is an abundant number, since it is smaller than the sum of its proper divisors (35165380).

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

28664540 is a wasteful number, since it uses less digits than its factorization.

28664540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 582 (or 580 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 35.

The square root of 28664540 is about 5353.9275303276. The cubic root of 28664540 is about 306.0424421743.

The spelling of 28664540 in words is "twenty-eight million, six hundred sixty-four thousand, five hundred forty".