1979 has 2 divisors, whose sum is σ = 1980.
Its totient is φ = 1978.
The previous prime is 1973. The next prime is 1987. The reversal of 1979 is 9791.
Subtracting from 1979 its sum of digits (26), we obtain a triangular number (1953 = T62).
1979 is nontrivially palindromic in base 3.
It is a weak prime.
It is an emirp because it is prime and its reverse (9791) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 1979 - 28 = 1723 is a prime.
It is a Chen prime.
It is a plaindrome in base 12, base 15 and base 16.
It is a nialpdrome in base 13.
It is not a weakly prime, because it can be changed into another prime (1973) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989 + 990.
It is an arithmetic number, because the mean of its divisors is an integer number (990).
21979 is an apocalyptic number.
1979 is a deficient number, since it is larger than the sum of its proper divisors (1).
1979 is an equidigital number, since it uses as much as digits as its factorization.
1979 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 567, while the sum is 26.
The square root of 1979 is about 44.4859528391.
The cubic root of 1979 is about 12.5549580152.
The spelling of 1979 in words is "one thousand, nine hundred seventy-nine".