21124220223340 has 96 divisors (see below), whose sum is σ = 48362497848000. Its totient is φ = 7703828545536.

The previous prime is 21124220223257. The next prime is 21124220223367. The reversal of 21124220223340 is 4332202242112.

It is a junction number, because it is equal to n+sod(n) for n = 21124220223299 and 21124220223308.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11745504 + ... + 13424056.

It is an arithmetic number, because the mean of its divisors is an integer number (503776019250).

Almost surely, 2^{21124220223340} is an apocalyptic number.

21124220223340 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 21124220223340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24181248924000).

21124220223340 is an abundant number, since it is smaller than the sum of its proper divisors (27238277624660).

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

21124220223340 is a wasteful number, since it uses less digits than its factorization.

21124220223340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1679171 (or 1679169 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 21124220223340 its reverse (4332202242112), we get a palindrome (25456422465452).

The spelling of 21124220223340 in words is "twenty-one trillion, one hundred twenty-four billion, two hundred twenty million, two hundred twenty-three thousand, three hundred forty".