21210111212122 has 32 divisors (see below), whose sum is σ = 36905873558400. Its totient is φ = 8954591041728.

The previous prime is 21210111212093. The next prime is 21210111212161. The reversal of 21210111212122 is 22121211101212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21210111212122.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39906972 + ... + 40434967.

It is an arithmetic number, because the mean of its divisors is an integer number (1153308548700).

Almost surely, 2^{21210111212122} is an apocalyptic number.

21210111212122 is a deficient number, since it is larger than the sum of its proper divisors (15695762346278).

21210111212122 is a wasteful number, since it uses less digits than its factorization.

21210111212122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80342230.

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

Adding to 21210111212122 its reverse (22121211101212), we get a palindrome (43331322313334).

The spelling of 21210111212122 in words is "twenty-one trillion, two hundred ten billion, one hundred eleven million, two hundred twelve thousand, one hundred twenty-two".