20100122012221 has 2 divisors, whose sum is σ = 20100122012222. Its totient is φ = 20100122012220.

The previous prime is 20100122012213. The next prime is 20100122012249. The reversal of 20100122012221 is 12221022100102.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11320835976025 + 8779286036196 = 3364645^2 + 2962986^2 .

It is a cyclic number.

It is not a de Polignac number, because 20100122012221 - 2³ = 20100122012213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20100122012195 and 20100122012204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20100122012281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050061006110 + 10050061006111.

It is an arithmetic number, because the mean of its divisors is an integer number (10050061006111).

Almost surely, 2^{20100122012221} is an apocalyptic number.

It is an amenable number.

20100122012221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20100122012221 is an equidigital number, since it uses as much as digits as its factorization.

20100122012221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20100122012221 its reverse (12221022100102), we get a palindrome (32321144112323).

The spelling of 20100122012221 in words is "twenty trillion, one hundred billion, one hundred twenty-two million, twelve thousand, two hundred twenty-one".