21210111012212 has 6 divisors (see below), whose sum is σ = 37117694271378. Its totient is φ = 10605055506104.

The previous prime is 21210111012173. The next prime is 21210111012221. The reversal of 21210111012212 is 21221011101212.

It can be written as a sum of positive squares in only one way, i.e., 19768392099556 + 1441718912656 = 4446166^2 + 1200716^2 .

It is a congruent number.

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 as a sum of consecutive naturals, namely, 2651263876523 + ... + 2651263876530.

It is an arithmetic number, because the mean of its divisors is an integer number (6186282378563).

Almost surely, 2^{21210111012212} is an apocalyptic number.

It is an amenable number.

21210111012212 is a deficient number, since it is larger than the sum of its proper divisors (15907583259166).

21210111012212 is a wasteful number, since it uses less digits than its factorization.

21210111012212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5302527753057 (or 5302527753055 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21210111012212 its reverse (21221011101212), we get a palindrome (42431122113424).

The spelling of 21210111012212 in words is "twenty-one trillion, two hundred ten billion, one hundred eleven million, twelve thousand, two hundred twelve".