16911979 has 4 divisors (see below), whose sum is σ = 19327984. Its totient is φ = 14495976.

The previous prime is 16911953. The next prime is 16912003. The reversal of 16911979 is 97911961.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97911961 = 7 ⋅13987423.

It is a cyclic number.

It is not a de Polignac number, because 16911979 - 2¹⁵ = 16879211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16911949) 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, 1207992 + ... + 1208005.

It is an arithmetic number, because the mean of its divisors is an integer number (4831996).

Almost surely, 2^16911979 is an apocalyptic number.

16911979 is a deficient number, since it is larger than the sum of its proper divisors (2416005).

16911979 is an equidigital number, since it uses as much as digits as its factorization.

16911979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2416004.

The product of its digits is 30618, while the sum is 43.

The square root of 16911979 is about 4112.4176587501. The cubic root of 16911979 is about 256.6836129438.

The spelling of 16911979 in words is "sixteen million, nine hundred eleven thousand, nine hundred seventy-nine".