21222102121949 has 2 divisors, whose sum is σ = 21222102121950. Its totient is φ = 21222102121948.

The previous prime is 21222102121931. The next prime is 21222102122057. The reversal of 21222102121949 is 94912120122212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18772783221049 + 2449318900900 = 4332757^2 + 1565030^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222102121949 - 2⁴⁰ = 20122590494173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222102123949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611051060974 + 10611051060975.

It is an arithmetic number, because the mean of its divisors is an integer number (10611051060975).

Almost surely, 2^{21222102121949} is an apocalyptic number.

It is an amenable number.

21222102121949 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222102121949 is an equidigital number, since it uses as much as digits as its factorization.

21222102121949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 38.

The spelling of 21222102121949 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred two million, one hundred twenty-one thousand, nine hundred forty-nine".