21121211212112 has 40 divisors (see below), whose sum is σ = 44646551238432. Its totient is φ = 9599692233600.

The previous prime is 21121211212097. The next prime is 21121211212117.

It is a happy number.

21121211212112 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21121211212112² (a number of 27 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121211212117) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 3388214 + ... + 7329557.

Almost surely, 2^{21121211212112} is an apocalyptic number.

21121211212112 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21121211212112 is an abundant number, since it is smaller than the sum of its proper divisors (23525340026320).

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

21121211212112 is a wasteful number, since it uses less digits than its factorization.

21121211212112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10728987 (or 10728981 counting only the distinct ones).

The product of its digits is 64, while the sum is 20.

It can be divided in two parts, 2112121 and 1212112, that added together give a palindrome (3324233).

The spelling of 21121211212112 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, two hundred twelve thousand, one hundred twelve".