219979 has 2 divisors, whose sum is σ = 219980. Its totient is φ = 219978.

The previous prime is 219977. The next prime is 219983. The reversal of 219979 is 979912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 219979 - 2¹ = 219977 is a prime.

Together with 219977, it forms a pair of twin primes.

It is a Chen prime.

219979 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (219971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109989 + 109990.

It is an arithmetic number, because the mean of its divisors is an integer number (109990).

2²¹⁹⁹⁷⁹ is an apocalyptic number.

219979 is a deficient number, since it is larger than the sum of its proper divisors (1).

219979 is an equidigital number, since it uses as much as digits as its factorization.

219979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10206, while the sum is 37.

The square root of 219979 is about 469.0191893729. The cubic root of 219979 is about 60.3661865034.

It can be divided in two parts, 2199 and 79, that added together give a triangular number (2278 = T₆₇).

The spelling of 219979 in words is "two hundred nineteen thousand, nine hundred seventy-nine".