28903680 has 216 divisors, whose sum is σ = 108254328. Its totient is φ = 7077888.

The previous prime is 28903673. The next prime is 28903681. The reversal of 28903680 is 8630982.

It can be written as a sum of positive squares in 4 ways, for example, as 2304 + 28901376 = 48^2 + 5376^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28903681) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 149664 + ... + 149856.

Almost surely, 2^28903680 is an apocalyptic number.

28903680 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 28903680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54127164).

28903680 is an abundant number, since it is smaller than the sum of its proper divisors (79350648).

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

28903680 is a wasteful number, since it uses less digits than its factorization.

28903680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 28903680 is about 5376.2142814438. The cubic root of 28903680 is about 306.8911609714.

The spelling of 28903680 in words is "twenty-eight million, nine hundred three thousand, six hundred eighty".