6821279075520 has 1680 divisors, whose sum is σ = 30249853444800. Its totient is φ = 1428598259712.

The previous prime is 6821279075519. The next prime is 6821279075557. The reversal of 6821279075520 is 255709721286.

6821279075520 is a `hidden beast` number, since 6 + 8 + 2 + 1 + 27 + 90 + 7 + 5 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (1680).

It is a super-2 number, since 2×6821279075520² (a number of 26 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 4568839894 + ... + 4568841386.

Almost surely, 2^{6821279075520} is an apocalyptic number.

6821279075520 is a gapful number since it is divisible by the number (60) 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 6821279075520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15124926722400).

6821279075520 is an abundant number, since it is smaller than the sum of its proper divisors (23428574369280).

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

6821279075520 is a wasteful number, since it uses less digits than its factorization.

6821279075520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1704 (or 1672 counting only the distinct ones).

The product of its (nonzero) digits is 4233600, while the sum is 54.

The spelling of 6821279075520 in words is "six trillion, eight hundred twenty-one billion, two hundred seventy-nine million, seventy-five thousand, five hundred twenty".