28221478272 has 320 divisors, whose sum is σ = 92908107600. Its totient is φ = 8447348736.

The previous prime is 28221478253. The next prime is 28221478273. The reversal of 28221478272 is 27287412282.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28221478273) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4984179 + ... + 4989837.

Almost surely, 2^28221478272 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 28221478272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46454053800).

28221478272 is an abundant number, since it is smaller than the sum of its proper divisors (64686629328).

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

28221478272 is a wasteful number, since it uses less digits than its factorization.

28221478272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5735 (or 5714 counting only the distinct ones).

The product of its digits is 401408, while the sum is 45.

The spelling of 28221478272 in words is "twenty-eight billion, two hundred twenty-one million, four hundred seventy-eight thousand, two hundred seventy-two".