189979 has 4 divisors (see below), whose sum is σ = 196560. Its totient is φ = 183400.

The previous prime is 189977. The next prime is 189983. The reversal of 189979 is 979981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 979981 = 83 ⋅11807.

It is a cyclic number.

It is not a de Polignac number, because 189979 - 2¹ = 189977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189977) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3247 + ... + 3304.

It is an arithmetic number, because the mean of its divisors is an integer number (49140).

2¹⁸⁹⁹⁷⁹ is an apocalyptic number.

189979 is a deficient number, since it is larger than the sum of its proper divisors (6581).

189979 is an equidigital number, since it uses as much as digits as its factorization.

189979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6580.

The product of its digits is 40824, while the sum is 43.

The square root of 189979 is about 435.8658050364. The cubic root of 189979 is about 57.4868526967.

The spelling of 189979 in words is "one hundred eighty-nine thousand, nine hundred seventy-nine".