28396477980 has 144 divisors (see below), whose sum is σ = 92829469824. Its totient is φ = 6984806400.

The previous prime is 28396477973. The next prime is 28396477981. The reversal of 28396477980 is 8977469382.

28396477980 is a `hidden beast` number, since 2 + 83 + 9 + 6 + 477 + 9 + 80 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28396477981) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3967405 + ... + 3974555.

It is an arithmetic number, because the mean of its divisors is an integer number (644649096).

Almost surely, 2^28396477980 is an apocalyptic number.

28396477980 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 28396477980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46414734912).

28396477980 is an abundant number, since it is smaller than the sum of its proper divisors (64432991844).

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

28396477980 is a wasteful number, since it uses less digits than its factorization.

28396477980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8876 (or 8871 counting only the distinct ones).

The product of its (nonzero) digits is 36578304, while the sum is 63.

The spelling of 28396477980 in words is "twenty-eight billion, three hundred ninety-six million, four hundred seventy-seven thousand, nine hundred eighty".