121020210121 has 2 divisors, whose sum is σ = 121020210122. Its totient is φ = 121020210120.

The previous prime is 121020210119. The next prime is 121020210149. The reversal of 121020210121 is 121012020121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 113426830521 + 7593379600 = 336789^2 + 87140^2 .

It is an emirp because it is prime and its reverse (121012020121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121020210121 - 2¹ = 121020210119 is a prime.

Together with 121020210119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (121020213121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60510105060 + 60510105061.

It is an arithmetic number, because the mean of its divisors is an integer number (60510105061).

Almost surely, 2^121020210121 is an apocalyptic number.

It is an amenable number.

121020210121 is a deficient number, since it is larger than the sum of its proper divisors (1).

121020210121 is an equidigital number, since it uses as much as digits as its factorization.

121020210121 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 121020210121 its reverse (121012020121), we get a palindrome (242032230242).

The spelling of 121020210121 in words is "one hundred twenty-one billion, twenty million, two hundred ten thousand, one hundred twenty-one".