28891722240 has 480 divisors, whose sum is σ = 108775180800. Its totient is φ = 7060193280.

The previous prime is 28891722239. The next prime is 28891722253. The reversal of 28891722240 is 4222719882.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×28891722240² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13569496 + ... + 13571624.

It is an arithmetic number, because the mean of its divisors is an integer number (226614960).

Almost surely, 2^28891722240 is an apocalyptic number.

28891722240 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 28891722240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54387590400).

28891722240 is an abundant number, since it is smaller than the sum of its proper divisors (79883458560).

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

28891722240 is a wasteful number, since it uses less digits than its factorization.

28891722240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2208 (or 2189 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The spelling of 28891722240 in words is "twenty-eight billion, eight hundred ninety-one million, seven hundred twenty-two thousand, two hundred forty".