121102019891 has 2 divisors, whose sum is σ = 121102019892. Its totient is φ = 121102019890.

The previous prime is 121102019881. The next prime is 121102019921. The reversal of 121102019891 is 198910201121.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (198910201121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121102019891 - 2¹⁰ = 121102018867 is a prime.

It is not a weakly prime, because it can be changed into another prime (121102019881) 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, 60551009945 + 60551009946.

It is an arithmetic number, because the mean of its divisors is an integer number (60551009946).

Almost surely, 2^121102019891 is an apocalyptic number.

121102019891 is a deficient number, since it is larger than the sum of its proper divisors (1).

121102019891 is an equidigital number, since it uses as much as digits as its factorization.

121102019891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 35.

The spelling of 121102019891 in words is "one hundred twenty-one billion, one hundred two million, nineteen thousand, eight hundred ninety-one".