21012112201 has 12 divisors (see below), whose sum is σ = 21723237396. Its totient is φ = 20323580160.

The previous prime is 21012112171. The next prime is 21012112241. The reversal of 21012112201 is 10221121012.

It can be written as a sum of positive squares in 2 ways, for example, as 322166601 + 20689945600 = 17949^2 + 143840^2 .

It is not a de Polignac number, because 21012112201 - 2¹⁹ = 21011587913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012112241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2295105 + ... + 2304241.

It is an arithmetic number, because the mean of its divisors is an integer number (1810269783).

Almost surely, 2^21012112201 is an apocalyptic number.

It is an amenable number.

21012112201 is a deficient number, since it is larger than the sum of its proper divisors (711125195).

21012112201 is an equidigital number, since it uses as much as digits as its factorization.

21012112201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11592 (or 11561 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21012112201 its reverse (10221121012), we get a palindrome (31233233213).

The spelling of 21012112201 in words is "twenty-one billion, twelve million, one hundred twelve thousand, two hundred one".