21214621043220 has 192 divisors, whose sum is σ = 66212902828800. Its totient is φ = 5031440793600.

The previous prime is 21214621043219. The next prime is 21214621043233. The reversal of 21214621043220 is 2234012641212.

It is a happy number.

It is a super-2 number, since 2×21214621043220² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11339140 + ... + 13076900.

It is an arithmetic number, because the mean of its divisors is an integer number (344858868900).

Almost surely, 2^{21214621043220} is an apocalyptic number.

21214621043220 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 21214621043220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33106451414400).

21214621043220 is an abundant number, since it is smaller than the sum of its proper divisors (44998281785580).

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

21214621043220 is a wasteful number, since it uses less digits than its factorization.

21214621043220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1738186 (or 1738184 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 30.

Adding to 21214621043220 its reverse (2234012641212), we get a palindrome (23448633684432).

The spelling of 21214621043220 in words is "twenty-one trillion, two hundred fourteen billion, six hundred twenty-one million, forty-three thousand, two hundred twenty".