221011009979 has 2 divisors, whose sum is σ = 221011009980. Its totient is φ = 221011009978.

The previous prime is 221011009949. The next prime is 221011009993. The reversal of 221011009979 is 979900110122.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221011009979 is a prime.

It is not a weakly prime, because it can be changed into another prime (221011009909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110505504989 + 110505504990.

It is an arithmetic number, because the mean of its divisors is an integer number (110505504990).

Almost surely, 2^221011009979 is an apocalyptic number.

221011009979 is a deficient number, since it is larger than the sum of its proper divisors (1).

221011009979 is an equidigital number, since it uses as much as digits as its factorization.

221011009979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20412, while the sum is 41.

The spelling of 221011009979 in words is "two hundred twenty-one billion, eleven million, nine thousand, nine hundred seventy-nine".