21011121021011 has 16 divisors (see below), whose sum is σ = 23543728178688. Its totient is φ = 18582396876000.

The previous prime is 21011121020963. The next prime is 21011121021019. The reversal of 21011121021011 is 11012012111012.

It is a cyclic number.

It is not a de Polignac number, because 21011121021011 - 2⁶ = 21011121020947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011121021019) 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, 115565 + ... + 6483486.

It is an arithmetic number, because the mean of its divisors is an integer number (1471483011168).

Almost surely, 2^{21011121021011} is an apocalyptic number.

21011121021011 is a deficient number, since it is larger than the sum of its proper divisors (2532607157677).

21011121021011 is a wasteful number, since it uses less digits than its factorization.

21011121021011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6606922.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21011121021011 its reverse (11012012111012), we get a palindrome (32023133132023).

The spelling of 21011121021011 in words is "twenty-one trillion, eleven billion, one hundred twenty-one million, twenty-one thousand, eleven".