21021122111010 has 128 divisors (see below), whose sum is σ = 59683145863680. Its totient is φ = 4636265926656.

The previous prime is 21021122110997. The next prime is 21021122111027. The reversal of 21021122111010 is 1011122112012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

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, 8753194 + ... + 10893146.

It is an arithmetic number, because the mean of its divisors is an integer number (466274577060).

Almost surely, 2^{21021122111010} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21021122111010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29841572931840).

21021122111010 is an abundant number, since it is smaller than the sum of its proper divisors (38662023752670).

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

21021122111010 is a wasteful number, since it uses less digits than its factorization.

21021122111010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2141612.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21021122111010 its reverse (1011122112012), we get a palindrome (22032244223022).

It can be divided in two parts, 210211 and 22111010, that added together give a triangular number (22321221 = T₆₆₈₁).

The spelling of 21021122111010 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-two million, one hundred eleven thousand, ten".