221211019979 has 2 divisors, whose sum is σ = 221211019980. Its totient is φ = 221211019978.

The previous prime is 221211019973. The next prime is 221211020011. The reversal of 221211019979 is 979910112122.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221211019979 is a prime.

It is not a weakly prime, because it can be changed into another prime (221211019973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110605509989 + 110605509990.

It is an arithmetic number, because the mean of its divisors is an integer number (110605509990).

Almost surely, 2^221211019979 is an apocalyptic number.

221211019979 is a deficient number, since it is larger than the sum of its proper divisors (1).

221211019979 is an equidigital number, since it uses as much as digits as its factorization.

221211019979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 44.

The spelling of 221211019979 in words is "two hundred twenty-one billion, two hundred eleven million, nineteen thousand, nine hundred seventy-nine".