28308280 has 192 divisors, whose sum is σ = 87907680. Its totient is φ = 8064000.

The previous prime is 28308257. The next prime is 28308299. The reversal of 28308280 is 8280382.

28308280 = T₁₆₉ + T₁₇₀ + ... + T₅₅₈.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 280230 + ... + 280330.

Almost surely, 2^28308280 is an apocalyptic number.

28308280 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 28308280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43953840).

28308280 is an abundant number, since it is smaller than the sum of its proper divisors (59599400).

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

28308280 is a wasteful number, since it uses less digits than its factorization.

28308280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 31.

The square root of 28308280 is about 5320.5526028788. The cubic root of 28308280 is about 304.7692602236.

The spelling of 28308280 in words is "twenty-eight million, three hundred eight thousand, two hundred eighty".