21200001111111 has 16 divisors (see below), whose sum is σ = 29030772747744. Its totient is φ = 13751285474304.

The previous prime is 21200001111103. The next prime is 21200001111131. The reversal of 21200001111111 is 11111110000212.

It is not a de Polignac number, because 21200001111111 - 2³ = 21200001111103 is a prime.

It is a super-2 number, since 2×21200001111111² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200001111131) 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, 34231075 + ... + 34844891.

It is an arithmetic number, because the mean of its divisors is an integer number (1814423296734).

Almost surely, 2^{21200001111111} is an apocalyptic number.

21200001111111 is a deficient number, since it is larger than the sum of its proper divisors (7830771636633).

21200001111111 is a wasteful number, since it uses less digits than its factorization.

21200001111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 925010.

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 21200001111111 its reverse (11111110000212), we get a palindrome (32311111111323).

The spelling of 21200001111111 in words is "twenty-one trillion, two hundred billion, one million, one hundred eleven thousand, one hundred eleven".