121944000821 has 2 divisors, whose sum is σ = 121944000822. Its totient is φ = 121944000820.

The previous prime is 121944000791. The next prime is 121944000847. The reversal of 121944000821 is 128000449121.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120331978321 + 1612022500 = 346889^2 + 40150^2 .

It is a cyclic number.

It is not a de Polignac number, because 121944000821 - 2¹⁰ = 121943999797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121944000881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60972000410 + 60972000411.

It is an arithmetic number, because the mean of its divisors is an integer number (60972000411).

Almost surely, 2^121944000821 is an apocalyptic number.

It is an amenable number.

121944000821 is a deficient number, since it is larger than the sum of its proper divisors (1).

121944000821 is an equidigital number, since it uses as much as digits as its factorization.

121944000821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 32.

Adding to 121944000821 its reverse (128000449121), we get a palindrome (249944449942).

The spelling of 121944000821 in words is "one hundred twenty-one billion, nine hundred forty-four million, eight hundred twenty-one", and thus it is an aban number.