1221199999079 has 2 divisors, whose sum is σ = 1221199999080. Its totient is φ = 1221199999078.

The previous prime is 1221199999073. The next prime is 1221199999081. The reversal of 1221199999079 is 9709999911221.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221199999079 is a prime.

Together with 1221199999081, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221199999073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610599999539 + 610599999540.

It is an arithmetic number, because the mean of its divisors is an integer number (610599999540).

Almost surely, 2^{1221199999079} is an apocalyptic number.

1221199999079 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221199999079 is an equidigital number, since it uses as much as digits as its factorization.

1221199999079 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14880348, while the sum is 68.

The spelling of 1221199999079 in words is "one trillion, two hundred twenty-one billion, one hundred ninety-nine million, nine hundred ninety-nine thousand, seventy-nine".