2117791 has 4 divisors (see below), whose sum is σ = 2280712. Its totient is φ = 1954872.

The previous prime is 2117777. The next prime is 2117813. The reversal of 2117791 is 1977112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2117791 - 2⁷ = 2117663 is a prime.

It is a Duffinian number.

2117791 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2117701) 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, 81441 + ... + 81466.

It is an arithmetic number, because the mean of its divisors is an integer number (570178).

2^2117791 is an apocalyptic number.

2117791 is a deficient number, since it is larger than the sum of its proper divisors (162921).

2117791 is a wasteful number, since it uses less digits than its factorization.

2117791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162920.

The product of its digits is 882, while the sum is 28.

The square root of 2117791 is about 1455.2632064338. The cubic root of 2117791 is about 128.4185315333.

The spelling of 2117791 in words is "two million, one hundred seventeen thousand, seven hundred ninety-one".