21121210221112 has 8 divisors (see below), whose sum is σ = 39602269164600. Its totient is φ = 10560605110552.

The previous prime is 21121210221071. The next prime is 21121210221121. The reversal of 21121210221112 is 21112201212112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21121210221112² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21121210221112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320075638812 + ... + 1320075638827.

It is an arithmetic number, because the mean of its divisors is an integer number (4950283645575).

Almost surely, 2^{21121210221112} is an apocalyptic number.

It is an amenable number.

21121210221112 is a deficient number, since it is larger than the sum of its proper divisors (18481058943488).

21121210221112 is a wasteful number, since it uses less digits than its factorization.

21121210221112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2640151277645 (or 2640151277641 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21121210221112 its reverse (21112201212112), we get a palindrome (42233411433224).

The spelling of 21121210221112 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred ten million, two hundred twenty-one thousand, one hundred twelve".