21011112122 has 128 divisors (see below), whose sum is σ = 44397158400. Its totient is φ = 7188445440.

The previous prime is 21011112097. The next prime is 21011112131. The reversal of 21011112122 is 22121111012.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21011112097 and 21011112106.

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, 9162008 + ... + 9164300.

It is an arithmetic number, because the mean of its divisors is an integer number (346852800).

Almost surely, 2^21011112122 is an apocalyptic number.

21011112122 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21011112122 is an abundant number, since it is smaller than the sum of its proper divisors (23386046278).

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

21011112122 is a wasteful number, since it uses less digits than its factorization.

21011112122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2548.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21011112122 its reverse (22121111012), we get a palindrome (43132223134).

The spelling of 21011112122 in words is "twenty-one billion, eleven million, one hundred twelve thousand, one hundred twenty-two".