21210201011111 has 16 divisors (see below), whose sum is σ = 25294478515200. Its totient is φ = 17389506064128.

The previous prime is 21210201011093. The next prime is 21210201011147. The reversal of 21210201011111 is 11111010201212.

It is a cyclic number.

It is not a de Polignac number, because 21210201011111 - 2¹⁰ = 21210201010087 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 (21210201011161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12325070 + ... + 13940148.

It is an arithmetic number, because the mean of its divisors is an integer number (1580904907200).

Almost surely, 2^{21210201011111} is an apocalyptic number.

21210201011111 is a deficient number, since it is larger than the sum of its proper divisors (4084277504089).

21210201011111 is a wasteful number, since it uses less digits than its factorization.

21210201011111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1696678.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21210201011111 its reverse (11111010201212), we get a palindrome (32321211212323).

The spelling of 21210201011111 in words is "twenty-one trillion, two hundred ten billion, two hundred one million, eleven thousand, one hundred eleven".