21121120111212 has 72 divisors (see below), whose sum is σ = 58339041825792. Its totient is φ = 6389795138400.

The previous prime is 21121120111199. The next prime is 21121120111213. The reversal of 21121120111212 is 21211102112112.

It is a happy number.

21121120111212 is a `hidden beast` number, since 211 + 211 + 20 + 1 + 11 + 212 = 666.

It is a super-2 number, since 2×21121120111212² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21121120111213) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43693864 + ... + 44174607.

Almost surely, 2^{21121120111212} is an apocalyptic number.

21121120111212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21121120111212 is an abundant number, since it is smaller than the sum of its proper divisors (37217921714580).

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

21121120111212 is a wasteful number, since it uses less digits than its factorization.

21121120111212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87869099 (or 87869094 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21121120111212 its reverse (21211102112112), we get a palindrome (42332222223324).

Subtracting 21121120111212 from its reverse (21211102112112), we obtain a square (89982000900 = 299970²).

The spelling of 21121120111212 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty million, one hundred eleven thousand, two hundred twelve".