21111010201 has 4 divisors (see below), whose sum is σ = 21838976100. Its totient is φ = 20383044304.

The previous prime is 21111010171. The next prime is 21111010223. The reversal of 21111010201 is 10201011112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15216456025 + 5894554176 = 123355^2 + 76776^2 .

It is a cyclic number.

It is not a de Polignac number, because 21111010201 - 2²³ = 21102621593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21111010241) 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 3 ways as a sum of consecutive naturals, for example, 363982906 + ... + 363982963.

It is an arithmetic number, because the mean of its divisors is an integer number (5459744025).

Almost surely, 2^21111010201 is an apocalyptic number.

It is an amenable number.

21111010201 is a deficient number, since it is larger than the sum of its proper divisors (727965899).

21111010201 is an equidigital number, since it uses as much as digits as its factorization.

21111010201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 727965898.

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

Adding to 21111010201 its reverse (10201011112), we get a palindrome (31312021313).

The spelling of 21111010201 in words is "twenty-one billion, one hundred eleven million, ten thousand, two hundred one".