21122111010 has 384 divisors, whose sum is σ = 70119302400. Its totient is φ = 4002324480.

The previous prime is 21122111009. The next prime is 21122111047. The reversal of 21122111010 is 1011122112.

It is a super-2 number, since 2×21122111010² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 18708126 + ... + 18709254.

It is an arithmetic number, because the mean of its divisors is an integer number (182602350).

Almost surely, 2^21122111010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21122111010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35059651200).

21122111010 is an abundant number, since it is smaller than the sum of its proper divisors (48997191390).

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

21122111010 is a wasteful number, since it uses less digits than its factorization.

21122111010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1266 (or 1259 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21122111010 its reverse (1011122112), we get a palindrome (22133233122).

The spelling of 21122111010 in words is "twenty-one billion, one hundred twenty-two million, one hundred eleven thousand, ten".