2117979 has 24 divisors (see below), whose sum is σ = 3294720. Its totient is φ = 1306368.

The previous prime is 2117977. The next prime is 2118007. The reversal of 2117979 is 9797112.

It is not a de Polignac number, because 2117979 - 2¹ = 2117977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2117971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16614 + ... + 16740.

It is an arithmetic number, because the mean of its divisors is an integer number (137280).

2^2117979 is an apocalyptic number.

2117979 is a deficient number, since it is larger than the sum of its proper divisors (1176741).

2117979 is a wasteful number, since it uses less digits than its factorization.

2117979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259 (or 256 counting only the distinct ones).

The product of its digits is 7938, while the sum is 36.

The square root of 2117979 is about 1455.3277981266. The cubic root of 2117979 is about 128.4223313999.

The spelling of 2117979 in words is "two million, one hundred seventeen thousand, nine hundred seventy-nine".