21210111201111 has 8 divisors (see below), whose sum is σ = 32320169449344. Its totient is φ = 12120063543480.

The previous prime is 21210111201017. The next prime is 21210111201131. The reversal of 21210111201111 is 11110211101212.

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

It is not a de Polignac number, because 21210111201111 - 2⁹ = 21210111200599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210111201131) 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, 505002647625 + ... + 505002647666.

It is an arithmetic number, because the mean of its divisors is an integer number (4040021181168).

Almost surely, 2^{21210111201111} is an apocalyptic number.

21210111201111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21210111201111 is a deficient number, since it is larger than the sum of its proper divisors (11110058248233).

21210111201111 is a wasteful number, since it uses less digits than its factorization.

21210111201111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1010005295301.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21210111201111 its reverse (11110211101212), we get a palindrome (32320322302323).

The spelling of 21210111201111 in words is "twenty-one trillion, two hundred ten billion, one hundred eleven million, two hundred one thousand, one hundred eleven".