28021455221760 has 4224 divisors, whose sum is σ = 138312220032000. Its totient is φ = 5231974809600.

The previous prime is 28021455221731. The next prime is 28021455221779. The reversal of 28021455221760 is 6712255412082.

28021455221760 is a `hidden beast` number, since 2 + 8 + 0 + 2 + 1 + 4 + 552 + 21 + 76 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (4224).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 383 ways as a sum of consecutive naturals, for example, 62408586016 + ... + 62408586464.

Almost surely, 2^{28021455221760} is an apocalyptic number.

28021455221760 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 28021455221760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69156110016000).

28021455221760 is an abundant number, since it is smaller than the sum of its proper divisors (110290764810240).

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

28021455221760 is a wasteful number, since it uses less digits than its factorization.

28021455221760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 531 counting only the distinct ones).

The product of its (nonzero) digits is 537600, while the sum is 45.

The spelling of 28021455221760 in words is "twenty-eight trillion, twenty-one billion, four hundred fifty-five million, two hundred twenty-one thousand, seven hundred sixty".