201979 has 2 divisors, whose sum is σ = 201980. Its totient is φ = 201978.

The previous prime is 201973. The next prime is 201997. The reversal of 201979 is 979102.

Together with next prime (201997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 201979 - 2⁵ = 201947 is a prime.

It is not a weakly prime, because it can be changed into another prime (201973) 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, 100989 + 100990.

It is an arithmetic number, because the mean of its divisors is an integer number (100990).

2²⁰¹⁹⁷⁹ is an apocalyptic number.

201979 is a deficient number, since it is larger than the sum of its proper divisors (1).

201979 is an equidigital number, since it uses as much as digits as its factorization.

201979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 28.

The square root of 201979 is about 449.4207382843. The cubic root of 201979 is about 58.6726097343.

The spelling of 201979 in words is "two hundred one thousand, nine hundred seventy-nine".