21021220012011 has 8 divisors (see below), whose sum is σ = 28028318347920. Its totient is φ = 14014134175392.

The previous prime is 21021220011997. The next prime is 21021220012021. The reversal of 21021220012011 is 11021002212012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21021220012011 - 2²⁶ = 21021152903147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21021220012021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2000121 + ... + 6785493.

It is an arithmetic number, because the mean of its divisors is an integer number (3503539793490).

Almost surely, 2^{21021220012011} is an apocalyptic number.

21021220012011 is a deficient number, since it is larger than the sum of its proper divisors (7007098335909).

21021220012011 is a wasteful number, since it uses less digits than its factorization.

21021220012011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6249645.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21021220012011 its reverse (11021002212012), we get a palindrome (32042222224023).

The spelling of 21021220012011 in words is "twenty-one trillion, twenty-one billion, two hundred twenty million, twelve thousand, eleven".