21010212121111 has 8 divisors (see below), whose sum is σ = 21012892617024. Its totient is φ = 21007531812960.

The previous prime is 21010212121103. The next prime is 21010212121127. The reversal of 21010212121111 is 11112121201012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21010212121111 - 2³ = 21010212121103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010212121141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 509775141 + ... + 509816353.

It is an arithmetic number, because the mean of its divisors is an integer number (2626611577128).

Almost surely, 2^{21010212121111} is an apocalyptic number.

21010212121111 is a deficient number, since it is larger than the sum of its proper divisors (2680495913).

21010212121111 is a wasteful number, since it uses less digits than its factorization.

21010212121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93881.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 21010212121111 its reverse (11112121201012), we get a palindrome (32122333322123).

The spelling of 21010212121111 in words is "twenty-one trillion, ten billion, two hundred twelve million, one hundred twenty-one thousand, one hundred eleven".