21011403783552 has 384 divisors, whose sum is σ = 70006130742240. Its totient is φ = 5534464868352.

The previous prime is 21011403783493. The next prime is 21011403783577. The reversal of 21011403783552 is 25538730411012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (42).

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 47 ways as a sum of consecutive naturals, for example, 194898688 + ... + 195006464.

Almost surely, 2^{21011403783552} 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 21011403783552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35003065371120).

21011403783552 is an abundant number, since it is smaller than the sum of its proper divisors (48994726958688).

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

21011403783552 is a wasteful number, since it uses less digits than its factorization.

21011403783552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108618 (or 108599 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 42.

The spelling of 21011403783552 in words is "twenty-one trillion, eleven billion, four hundred three million, seven hundred eighty-three thousand, five hundred fifty-two".