28273838372820 has 144 divisors (see below), whose sum is σ = 88091023417488. Its totient is φ = 7335156787200.

The previous prime is 28273838372749. The next prime is 28273838372849. The reversal of 28273838372820 is 2827383837282.

It is a happy number.

28273838372820 is a `hidden beast` number, since 2 + 8 + 273 + 8 + 3 + 83 + 7 + 282 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 527450682564 + 27746387690256 = 726258^2 + 5267484^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 65726272 + ... + 66155048.

It is an arithmetic number, because the mean of its divisors is an integer number (611743218177).

Almost surely, 2^{28273838372820} is an apocalyptic number.

28273838372820 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 28273838372820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44045511708744).

28273838372820 is an abundant number, since it is smaller than the sum of its proper divisors (59817185044668).

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

28273838372820 is a wasteful number, since it uses less digits than its factorization.

28273838372820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438730 (or 438725 counting only the distinct ones).

The product of its (nonzero) digits is 86704128, while the sum is 63.

The spelling of 28273838372820 in words is "twenty-eight trillion, two hundred seventy-three billion, eight hundred thirty-eight million, three hundred seventy-two thousand, eight hundred twenty".