21313012218624 has 288 divisors, whose sum is σ = 73016813219840. Its totient is φ = 6006014189568.

The previous prime is 21313012218623. The next prime is 21313012218677. The reversal of 21313012218624 is 42681221031312.

21313012218624 is a `hidden beast` number, since 2 + 1 + 3 + 1 + 3 + 0 + 1 + 2 + 21 + 8 + 624 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is not an unprimeable number, because it can be changed into a prime (21313012218623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 514929 + ... + 6549135.

Almost surely, 2^{21313012218624} is an apocalyptic number.

21313012218624 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 21313012218624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36508406609920).

21313012218624 is an abundant number, since it is smaller than the sum of its proper divisors (51703801001216).

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

21313012218624 is an equidigital number, since it uses as much as digits as its factorization.

21313012218624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6034312 (or 6034292 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

Adding to 21313012218624 its reverse (42681221031312), we get a palindrome (63994233249936).

The spelling of 21313012218624 in words is "twenty-one trillion, three hundred thirteen billion, twelve million, two hundred eighteen thousand, six hundred twenty-four".