100121201221 has 2 divisors, whose sum is σ = 100121201222. Its totient is φ = 100121201220.

The previous prime is 100121201209. The next prime is 100121201231. The reversal of 100121201221 is 122102121001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72840072321 + 27281128900 = 269889^2 + 165170^2 .

It is a cyclic number.

It is not a de Polignac number, because 100121201221 - 2⁷ = 100121201093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100121201231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50060600610 + 50060600611.

It is an arithmetic number, because the mean of its divisors is an integer number (50060600611).

Almost surely, 2^100121201221 is an apocalyptic number.

It is an amenable number.

100121201221 is a deficient number, since it is larger than the sum of its proper divisors (1).

100121201221 is an equidigital number, since it uses as much as digits as its factorization.

100121201221 is an evil number, because the sum of its binary digits is even.

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

Adding to 100121201221 its reverse (122102121001), we get a palindrome (222223322222).

The spelling of 100121201221 in words is "one hundred billion, one hundred twenty-one million, two hundred one thousand, two hundred twenty-one".