20101010221 has 4 divisors (see below), whose sum is σ = 20101340700. Its totient is φ = 20100679744.

The previous prime is 20101010219. The next prime is 20101010227. The reversal of 20101010221 is 12201010102.

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 12614434596 + 7486575625 = 112314^2 + 86525^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101010221 - 2¹ = 20101010219 is a prime.

It is a super-2 number, since 2×20101010221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20101010198 and 20101010207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101010227) 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, 44686 + ... + 205423.

It is an arithmetic number, because the mean of its divisors is an integer number (5025335175).

Almost surely, 2^20101010221 is an apocalyptic number.

It is an amenable number.

20101010221 is a deficient number, since it is larger than the sum of its proper divisors (330479).

20101010221 is an equidigital number, since it uses as much as digits as its factorization.

20101010221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330478.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20101010221 its reverse (12201010102), we get a palindrome (32302020323).

The spelling of 20101010221 in words is "twenty billion, one hundred one million, ten thousand, two hundred twenty-one".