21022111212 has 24 divisors (see below), whose sum is σ = 49557282096. Its totient is φ = 6935129088.

The previous prime is 21022111207. The next prime is 21022111217. The reversal of 21022111212 is 21211122012.

It is an interprime number because it is at equal distance from previous prime (21022111207) and next prime (21022111217).

It is a super-3 number, since 3×21022111212³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 21022111191 and 21022111200.

It is not an unprimeable number, because it can be changed into a prime (21022111217) 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, 9028953 + ... + 9031280.

It is an arithmetic number, because the mean of its divisors is an integer number (2064886754).

Almost surely, 2^21022111212 is an apocalyptic number.

It is an amenable number.

21022111212 is an abundant number, since it is smaller than the sum of its proper divisors (28535170884).

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

21022111212 is a wasteful number, since it uses less digits than its factorization.

21022111212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18060337 (or 18060335 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21022111212 its reverse (21211122012), we get a palindrome (42233233224).

The spelling of 21022111212 in words is "twenty-one billion, twenty-two million, one hundred eleven thousand, two hundred twelve".