21011011111211 has 8 divisors (see below), whose sum is σ = 23454151938624. Its totient is φ = 18656711768520.

The previous prime is 21011011111151. The next prime is 21011011111271. The reversal of 21011011111211 is 11211111011012.

It is an interprime number because it is at equal distance from previous prime (21011011111151) and next prime (21011011111271).

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 21011011111211 - 2⁶ = 21011011111147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21011011111271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22210370681 + ... + 22210371626.

It is an arithmetic number, because the mean of its divisors is an integer number (2931768992328).

Almost surely, 2^{21011011111211} is an apocalyptic number.

21011011111211 is a deficient number, since it is larger than the sum of its proper divisors (2443140827413).

21011011111211 is a wasteful number, since it uses less digits than its factorization.

21011011111211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44420742361.

The product of its (nonzero) digits is 4, while the sum is 14.

Adding to 21011011111211 its reverse (11211111011012), we get a palindrome (32222122122223).

The spelling of 21011011111211 in words is "twenty-one trillion, eleven billion, eleven million, one hundred eleven thousand, two hundred eleven".