1211351242109 has 2 divisors, whose sum is σ = 1211351242110. Its totient is φ = 1211351242108.

The previous prime is 1211351242039. The next prime is 1211351242141. The reversal of 1211351242109 is 9012421531121.

It is an a-pointer prime, because the next prime (1211351242141) can be obtained adding 1211351242109 to its sum of digits (32).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 730089929209 + 481261312900 = 854453^2 + 693730^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211351242109 - 2²⁰ = 1211350193533 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211351262109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605675621054 + 605675621055.

It is an arithmetic number, because the mean of its divisors is an integer number (605675621055).

Almost surely, 2^{1211351242109} is an apocalyptic number.

It is an amenable number.

1211351242109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211351242109 is an equidigital number, since it uses as much as digits as its factorization.

1211351242109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 32.

The spelling of 1211351242109 in words is "one trillion, two hundred eleven billion, three hundred fifty-one million, two hundred forty-two thousand, one hundred nine".