221121210111212 has 12 divisors (see below), whose sum is σ = 399444766652736. Its totient is φ = 106994133924720.

The previous prime is 221121210111203. The next prime is 221121210111223. The reversal of 221121210111212 is 212111012121122.

It is a happy number.

It is a super-2 number, since 2×221121210111212² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 891617782583 + ... + 891617782830.

It is an arithmetic number, because the mean of its divisors is an integer number (33287063887728).

Almost surely, 2^{221121210111212} is an apocalyptic number.

It is an amenable number.

221121210111212 is a deficient number, since it is larger than the sum of its proper divisors (178323556541524).

221121210111212 is a wasteful number, since it uses less digits than its factorization.

221121210111212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1783235565448 (or 1783235565446 counting only the distinct ones).

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

Adding to 221121210111212 its reverse (212111012121122), we get a palindrome (433232222232334).

The spelling of 221121210111212 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, two hundred ten million, one hundred eleven thousand, two hundred twelve".