21242321565120 has 1120 divisors, whose sum is σ = 86936247889920. Its totient is φ = 4887816929280.

The previous prime is 21242321565119. The next prime is 21242321565161. The reversal of 21242321565120 is 2156512324212.

21242321565120 is a `hidden beast` number, since 2 + 1 + 2 + 42 + 32 + 1 + 565 + 1 + 20 = 666.

It is a super-2 number, since 2×21242321565120² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 259496037 + ... + 259577883.

Almost surely, 2^{21242321565120} is an apocalyptic number.

21242321565120 is a gapful number since it is divisible by the number (20) 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 21242321565120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43468123944960).

21242321565120 is an abundant number, since it is smaller than the sum of its proper divisors (65693926324800).

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

21242321565120 is a wasteful number, since it uses less digits than its factorization.

21242321565120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81943 (or 81924 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

Adding to 21242321565120 its reverse (2156512324212), we get a palindrome (23398833889332).

The spelling of 21242321565120 in words is "twenty-one trillion, two hundred forty-two billion, three hundred twenty-one million, five hundred sixty-five thousand, one hundred twenty".