121220020261 has 2 divisors, whose sum is σ = 121220020262. Its totient is φ = 121220020260.

The previous prime is 121220020199. The next prime is 121220020297. The reversal of 121220020261 is 162020022121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 113208696225 + 8011324036 = 336465^2 + 89506^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121220020261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121220020861) 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 as a sum of consecutive naturals, namely, 60610010130 + 60610010131.

It is an arithmetic number, because the mean of its divisors is an integer number (60610010131).

Almost surely, 2^121220020261 is an apocalyptic number.

It is an amenable number.

121220020261 is a deficient number, since it is larger than the sum of its proper divisors (1).

121220020261 is an equidigital number, since it uses as much as digits as its factorization.

121220020261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 121220020261 its reverse (162020022121), we get a palindrome (283240042382).

The spelling of 121220020261 in words is "one hundred twenty-one billion, two hundred twenty million, twenty thousand, two hundred sixty-one".