21001022122002 has 64 divisors (see below), whose sum is σ = 45558195481344. Its totient is φ = 6415440537600.

The previous prime is 21001022122001. The next prime is 21001022122021. The reversal of 21001022122002 is 20022122010012.

It is not an unprimeable number, because it can be changed into a prime (21001022122001) 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, 20427798 + ... + 21431214.

It is an arithmetic number, because the mean of its divisors is an integer number (711846804396).

Almost surely, 2^{21001022122002} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21001022122002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22779097740672).

21001022122002 is an abundant number, since it is smaller than the sum of its proper divisors (24557173359342).

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

21001022122002 is a wasteful number, since it uses less digits than its factorization.

21001022122002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005363.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21001022122002 its reverse (20022122010012), we get a palindrome (41023144132014).

The spelling of 21001022122002 in words is "twenty-one trillion, one billion, twenty-two million, one hundred twenty-two thousand, two".