21144764019456 has 504 divisors, whose sum is σ = 78896404925184. Its totient is φ = 5492142766080.

The previous prime is 21144764019389. The next prime is 21144764019493. The reversal of 21144764019456 is 65491046744112.

21144764019456 is a `hidden beast` number, since 2 + 1 + 1 + 447 + 6 + 4 + 0 + 194 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (504).

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

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 13634325 + ... + 15105771.

Almost surely, 2^{21144764019456} 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 21144764019456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39448202462592).

21144764019456 is an abundant number, since it is smaller than the sum of its proper divisors (57751640905728).

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

21144764019456 is an equidigital number, since it uses as much as digits as its factorization.

21144764019456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1471499 (or 1471470 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 21144764019456 in words is "twenty-one trillion, one hundred forty-four billion, seven hundred sixty-four million, nineteen thousand, four hundred fifty-six".