28663808 has 28 divisors (see below), whose sum is σ = 57340500. Its totient is φ = 14327808.

The previous prime is 28663787. The next prime is 28663813. The reversal of 28663808 is 80836682.

It is a super-2 number, since 2×28663808² = 1643227778121728, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6443 + ... + 9941.

It is an arithmetic number, because the mean of its divisors is an integer number (2047875).

Almost surely, 2^28663808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28663808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28670250).

28663808 is an abundant number, since it is smaller than the sum of its proper divisors (28676692).

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

28663808 is an frugal number, since it uses more digits than its factorization.

28663808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3525 (or 3501 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 41.

The square root of 28663808 is about 5353.8591688613. The cubic root of 28663808 is about 306.0398370395.

The spelling of 28663808 in words is "twenty-eight million, six hundred sixty-three thousand, eight hundred eight".