100212102121721 has 2 divisors, whose sum is σ = 100212102121722. Its totient is φ = 100212102121720.

The previous prime is 100212102121687. The next prime is 100212102121787. The reversal of 100212102121721 is 127121201212001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70877540454400 + 29334561667321 = 8418880^2 + 5416139^2 .

It is a cyclic number.

It is not a de Polignac number, because 100212102121721 - 2³⁰ = 100211028379897 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (100212102129721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50106051060860 + 50106051060861.

It is an arithmetic number, because the mean of its divisors is an integer number (50106051060861).

Almost surely, 2^{100212102121721} is an apocalyptic number.

It is an amenable number.

100212102121721 is a deficient number, since it is larger than the sum of its proper divisors (1).

100212102121721 is an equidigital number, since it uses as much as digits as its factorization.

100212102121721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 23.

Adding to 100212102121721 its reverse (127121201212001), we get a palindrome (227333303333722).

The spelling of 100212102121721 in words is "one hundred trillion, two hundred twelve billion, one hundred two million, one hundred twenty-one thousand, seven hundred twenty-one".