21121110220949 has 2 divisors, whose sum is σ = 21121110220950. Its totient is φ = 21121110220948.

The previous prime is 21121110220933. The next prime is 21121110221033. The reversal of 21121110220949 is 94902201112112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15641882620324 + 5479227600625 = 3954982^2 + 2340775^2 .

It is a cyclic number.

It is not a de Polignac number, because 21121110220949 - 2⁴ = 21121110220933 is a prime.

It is a super-2 number, since 2×21121110220949² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121110220649) 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, 10560555110474 + 10560555110475.

It is an arithmetic number, because the mean of its divisors is an integer number (10560555110475).

Almost surely, 2^{21121110220949} is an apocalyptic number.

It is an amenable number.

21121110220949 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121110220949 is an equidigital number, since it uses as much as digits as its factorization.

21121110220949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 35.

The spelling of 21121110220949 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred ten million, two hundred twenty thousand, nine hundred forty-nine".