12121991443 has 2 divisors, whose sum is σ = 12121991444. Its totient is φ = 12121991442.

The previous prime is 12121991419. The next prime is 12121991447. The reversal of 12121991443 is 34419912121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12121991443 - 2²⁹ = 11585120531 is a prime.

It is not a weakly prime, because it can be changed into another prime (12121991447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6060995721 + 6060995722.

It is an arithmetic number, because the mean of its divisors is an integer number (6060995722).

Almost surely, 2^12121991443 is an apocalyptic number.

12121991443 is a deficient number, since it is larger than the sum of its proper divisors (1).

12121991443 is an equidigital number, since it uses as much as digits as its factorization.

12121991443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 37.

The spelling of 12121991443 in words is "twelve billion, one hundred twenty-one million, nine hundred ninety-one thousand, four hundred forty-three".