21353570543744 has 128 divisors (see below), whose sum is σ = 44254808136000. Its totient is φ = 10254844293120.

The previous prime is 21353570543743. The next prime is 21353570543803. The reversal of 21353570543744 is 44734507535312.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (21353570543743) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1993978262 + ... + 1993988970.

Almost surely, 2^{21353570543744} 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 21353570543744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22127404068000).

21353570543744 is an abundant number, since it is smaller than the sum of its proper divisors (22901237592256).

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

21353570543744 is a wasteful number, since it uses less digits than its factorization.

21353570543744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16766 (or 16754 counting only the distinct ones).

The product of its (nonzero) digits is 21168000, while the sum is 53.

The spelling of 21353570543744 in words is "twenty-one trillion, three hundred fifty-three billion, five hundred seventy million, five hundred forty-three thousand, seven hundred forty-four".