28121948416 has 81 divisors (see below), whose sum is σ = 57612143631. Its totient is φ = 13700092416.

The previous prime is 28121948389. The next prime is 28121948417. The reversal of 28121948416 is 61484912182.

The square root of 28121948416 is 167696.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28121948417) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 126107281 + ... + 126107503.

Almost surely, 2^28121948416 is an apocalyptic number.

28121948416 is the 167696-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28121948416

28121948416 is an abundant number, since it is smaller than the sum of its proper divisors (29490195215).

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

28121948416 is an frugal number, since it uses more digits than its factorization.

28121948416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 556 (or 272 counting only the distinct ones).

The product of its digits is 221184, while the sum is 46.

The spelling of 28121948416 in words is "twenty-eight billion, one hundred twenty-one million, nine hundred forty-eight thousand, four hundred sixteen".