21280626851328 has 560 divisors, whose sum is σ = 68722075255680. Its totient is φ = 6541419036672.

The previous prime is 21280626851327. The next prime is 21280626851383. The reversal of 21280626851328 is 82315862608212.

21280626851328 is a `hidden beast` number, since 2 + 1 + 2 + 8 + 0 + 6 + 268 + 51 + 328 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21280626851327) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 7826635953 + ... + 7826638671.

It is an arithmetic number, because the mean of its divisors is an integer number (122717991528).

Almost surely, 2^{21280626851328} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21280626851328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34361037627840).

21280626851328 is an abundant number, since it is smaller than the sum of its proper divisors (47441448404352).

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

21280626851328 is an equidigital number, since it uses as much as digits as its factorization.

21280626851328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4381 (or 4350 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 54.

The spelling of 21280626851328 in words is "twenty-one trillion, two hundred eighty billion, six hundred twenty-six million, eight hundred fifty-one thousand, three hundred twenty-eight".