28138451904 has 168 divisors, whose sum is σ = 82168605792. Its totient is φ = 9204572160.

The previous prime is 28138451899. The next prime is 28138451921. The reversal of 28138451904 is 40915483182.

28138451904 is a `hidden beast` number, since 2 + 81 + 38 + 451 + 90 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 28138451904.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9527292 + ... + 9530244.

It is an arithmetic number, because the mean of its divisors is an integer number (489098844).

Almost surely, 2^28138451904 is an apocalyptic number.

28138451904 is a gapful number since it is divisible by the number (24) 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 28138451904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41084302896).

28138451904 is an abundant number, since it is smaller than the sum of its proper divisors (54030153888).

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

28138451904 is a wasteful number, since it uses less digits than its factorization.

28138451904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3275 (or 3262 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 28138451904 in words is "twenty-eight billion, one hundred thirty-eight million, four hundred fifty-one thousand, nine hundred four".