21112112201 has 16 divisors (see below), whose sum is σ = 23187027600. Its totient is φ = 19133442048.

The previous prime is 21112112173. The next prime is 21112112237. The reversal of 21112112201 is 10221121112.

It can be written as a sum of positive squares in 8 ways, for example, as 2099838976 + 19012273225 = 45824^2 + 137885^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112112201 - 2³⁰ = 20038370377 is a prime.

It is a super-2 number, since 2×21112112201² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21112111201) 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, 126485 + ... + 241293.

It is an arithmetic number, because the mean of its divisors is an integer number (1449189225).

Almost surely, 2^21112112201 is an apocalyptic number.

It is an amenable number.

21112112201 is a deficient number, since it is larger than the sum of its proper divisors (2074915399).

21112112201 is a wasteful number, since it uses less digits than its factorization.

21112112201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115228.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21112112201 its reverse (10221121112), we get a palindrome (31333233313).

It can be divided in two parts, 211121 and 12201, that added together give a palindrome (223322).

The spelling of 21112112201 in words is "twenty-one billion, one hundred twelve million, one hundred twelve thousand, two hundred one".