20100221122221 has 12 divisors (see below), whose sum is σ = 29300016520060. Its totient is φ = 13277210281920.

The previous prime is 20100221122211. The next prime is 20100221122243. The reversal of 20100221122221 is 12222112200102.

It is a happy number.

20100221122221 is a `hidden beast` number, since 2 + 0 + 100 + 221 + 122 + 221 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8269276653225 + 11830944468996 = 2875635^2 + 3439614^2 .

It is not a de Polignac number, because 20100221122221 - 2¹⁸ = 20100220860077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20100221122194 and 20100221122203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100221122211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10244760040 + ... + 10244762001.

Almost surely, 2^{20100221122221} is an apocalyptic number.

It is an amenable number.

20100221122221 is a deficient number, since it is larger than the sum of its proper divisors (9199795397839).

20100221122221 is a wasteful number, since it uses less digits than its factorization.

20100221122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20489522156 (or 20489522153 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 20100221122221 its reverse (12222112200102), we get a palindrome (32322333322323).

The spelling of 20100221122221 in words is "twenty trillion, one hundred billion, two hundred twenty-one million, one hundred twenty-two thousand, two hundred twenty-one".