21201211011 has 16 divisors (see below), whose sum is σ = 29038672800. Its totient is φ = 13749113088.

The previous prime is 21201211001. The next prime is 21201211063. The reversal of 21201211011 is 11011210212.

It is not a de Polignac number, because 21201211011 - 2¹³ = 21201202819 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21201211001) 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 15 ways as a sum of consecutive naturals, for example, 557575 + ... + 594383.

It is an arithmetic number, because the mean of its divisors is an integer number (1814917050).

Almost surely, 2^21201211011 is an apocalyptic number.

21201211011 is a deficient number, since it is larger than the sum of its proper divisors (7837461789).

21201211011 is a wasteful number, since it uses less digits than its factorization.

21201211011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42038.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21201211011 its reverse (11011210212), we get a palindrome (32212421223).

The spelling of 21201211011 in words is "twenty-one billion, two hundred one million, two hundred eleven thousand, eleven".