21000111011 has 8 divisors (see below), whose sum is σ = 23699185200. Its totient is φ = 18432699040.

The previous prime is 21000110993. The next prime is 21000111017. The reversal of 21000111011 is 11011100012.

It is a happy number.

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 21000111011 - 2²² = 20995916707 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21000111011.

It is not an unprimeable number, because it can be changed into a prime (21000111017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32915216 + ... + 32915853.

It is an arithmetic number, because the mean of its divisors is an integer number (2962398150).

Almost surely, 2^21000111011 is an apocalyptic number.

21000111011 is a deficient number, since it is larger than the sum of its proper divisors (2699074189).

21000111011 is a wasteful number, since it uses less digits than its factorization.

21000111011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65831109.

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 21000111011 its reverse (11011100012), we get a palindrome (32011211023).

The spelling of 21000111011 in words is "twenty-one billion, one hundred eleven thousand, eleven".