21112001011 has 4 divisors (see below), whose sum is σ = 21125632000. Its totient is φ = 21098370024.

The previous prime is 21112000967. The next prime is 21112001033. The reversal of 21112001011 is 11010021112.

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 21112001011 - 2⁷ = 21112000883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21112001041) 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, 6813171 + ... + 6816268.

It is an arithmetic number, because the mean of its divisors is an integer number (5281408000).

Almost surely, 2^21112001011 is an apocalyptic number.

21112001011 is a deficient number, since it is larger than the sum of its proper divisors (13630989).

21112001011 is a wasteful number, since it uses less digits than its factorization.

21112001011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13630988.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21112001011 its reverse (11010021112), we get a palindrome (32122022123).

The spelling of 21112001011 in words is "twenty-one billion, one hundred twelve million, one thousand, eleven".