28122880 has 72 divisors (see below), whose sum is σ = 68285952. Its totient is φ = 11096064.

The previous prime is 28122877. The next prime is 28122883. The reversal of 28122880 is 8822182.

It is an interprime number because it is at equal distance from previous prime (28122877) and next prime (28122883).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28122883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162474 + ... + 162646.

It is an arithmetic number, because the mean of its divisors is an integer number (948416).

Almost surely, 2^28122880 is an apocalyptic number.

28122880 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 28122880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34142976).

28122880 is an abundant number, since it is smaller than the sum of its proper divisors (40163072).

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

28122880 is a wasteful number, since it uses less digits than its factorization.

28122880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321 (or 307 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 31.

The square root of 28122880 is about 5303.1009796156. The cubic root of 28122880 is about 304.1024585388.

The spelling of 28122880 in words is "twenty-eight million, one hundred twenty-two thousand, eight hundred eighty".