21001200110111 has 4 divisors (see below), whose sum is σ = 22616677041672. Its totient is φ = 19385723178552.

The previous prime is 21001200110041. The next prime is 21001200110113. The reversal of 21001200110111 is 11101100210012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21001200110111 - 2²² = 21001195915807 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001200110092 and 21001200110101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001200110113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 807738465761 + ... + 807738465786.

It is an arithmetic number, because the mean of its divisors is an integer number (5654169260418).

Almost surely, 2^{21001200110111} is an apocalyptic number.

21001200110111 is a deficient number, since it is larger than the sum of its proper divisors (1615476931561).

21001200110111 is a wasteful number, since it uses less digits than its factorization.

21001200110111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1615476931560.

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

Adding to 21001200110111 its reverse (11101100210012), we get a palindrome (32102300320123).

Subtracting from 21001200110111 its reverse (11101100210012), we obtain a palindrome (9900099900099).

The spelling of 21001200110111 in words is "twenty-one trillion, one billion, two hundred million, one hundred ten thousand, one hundred eleven".