21660196583424 has 384 divisors, whose sum is σ = 69583592332800. Its totient is φ = 5853271818240.

The previous prime is 21660196583387. The next prime is 21660196583429. The reversal of 21660196583424 is 42438569106612.

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 (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21660196583429) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 504161304 + ... + 504204264.

It is an arithmetic number, because the mean of its divisors is an integer number (181207271700).

Almost surely, 2^{21660196583424} is an apocalyptic number.

21660196583424 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 21660196583424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34791796166400).

21660196583424 is an abundant number, since it is smaller than the sum of its proper divisors (47923395749376).

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

21660196583424 is a wasteful number, since it uses less digits than its factorization.

21660196583424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43629 (or 43609 counting only the distinct ones).

The product of its (nonzero) digits is 14929920, while the sum is 57.

The spelling of 21660196583424 in words is "twenty-one trillion, six hundred sixty billion, one hundred ninety-six million, five hundred eighty-three thousand, four hundred twenty-four".