21001001201111 has 8 divisors (see below), whose sum is σ = 21008910753600. Its totient is φ = 20993092849152.

The previous prime is 21001001201099. The next prime is 21001001201113. The reversal of 21001001201111 is 11110210010012.

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 21001001201111 - 2²² = 21000997006807 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001001201092 and 21001001201101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001001201113) 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, 35492615 + ... + 36079463.

It is an arithmetic number, because the mean of its divisors is an integer number (2626113844200).

Almost surely, 2^{21001001201111} is an apocalyptic number.

21001001201111 is a deficient number, since it is larger than the sum of its proper divisors (7909552489).

21001001201111 is an equidigital number, since it uses as much as digits as its factorization.

21001001201111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600265.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21001001201111 its reverse (11110210010012), we get a palindrome (32111211211123).

The spelling of 21001001201111 in words is "twenty-one trillion, one billion, one million, two hundred one thousand, one hundred eleven".