21121222212112 has 120 divisors (see below), whose sum is σ = 45174349156608. Its totient is φ = 9559272898560.

The previous prime is 21121222212067. The next prime is 21121222212143.

21121222212112 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21121222212112² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1456327453 + ... + 1456341955.

Almost surely, 2^{21121222212112} is an apocalyptic number.

21121222212112 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121222212112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22587174578304).

21121222212112 is an abundant number, since it is smaller than the sum of its proper divisors (24053126944496).

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

21121222212112 is a wasteful number, since it uses less digits than its factorization.

21121222212112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17717 (or 17700 counting only the distinct ones).

The product of its digits is 256, while the sum is 22.

Multiplying 21121222212112 by its sum of digits (22), we get a palindrome (464666888666464).

It can be divided in two parts, 2112122 and 2212112, that added together give a palindrome (4324234).

The spelling of 21121222212112 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twenty-two million, two hundred twelve thousand, one hundred twelve".