21234020022 has 64 divisors (see below), whose sum is σ = 47842488000. Its totient is φ = 6980198400.

The previous prime is 21234020009. The next prime is 21234020099. The reversal of 21234020022 is 22002043212.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21234019977 and 21234020004.

It is a congruent number.

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, 1394104 + ... + 1409252.

It is an arithmetic number, because the mean of its divisors is an integer number (747538875).

Almost surely, 2^21234020022 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21234020022, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23921244000).

21234020022 is an abundant number, since it is smaller than the sum of its proper divisors (26608467978).

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

21234020022 is a wasteful number, since it uses less digits than its factorization.

21234020022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15518 (or 15512 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

Adding to 21234020022 its reverse (22002043212), we get a palindrome (43236063234).

The spelling of 21234020022 in words is "twenty-one billion, two hundred thirty-four million, twenty thousand, twenty-two".