21771299505984 has 1344 divisors, whose sum is σ = 75592116633600. Its totient is φ = 5488835788800.

The previous prime is 21771299505937. The next prime is 21771299506009. The reversal of 21771299505984 is 48950599217712.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a congruent number.

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 191 ways as a sum of consecutive naturals, for example, 17948308962 + ... + 17948310174.

It is an arithmetic number, because the mean of its divisors is an integer number (56244134400).

Almost surely, 2^{21771299505984} is an apocalyptic number.

21771299505984 is a gapful number since it is divisible by the number (24) 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 21771299505984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37796058316800).

21771299505984 is an abundant number, since it is smaller than the sum of its proper divisors (53820817127616).

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

21771299505984 is a wasteful number, since it uses less digits than its factorization.

21771299505984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1412 (or 1395 counting only the distinct ones).

The product of its (nonzero) digits is 114307200, while the sum is 69.

The spelling of 21771299505984 in words is "twenty-one trillion, seven hundred seventy-one billion, two hundred ninety-nine million, five hundred five thousand, nine hundred eighty-four".