2117811 has 4 divisors (see below), whose sum is σ = 2823752. Its totient is φ = 1411872.

The previous prime is 2117777. The next prime is 2117813. The reversal of 2117811 is 1187112.

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

It is not a de Polignac number, because 2117811 - 2⁶ = 2117747 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2117813) 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, 352966 + ... + 352971.

It is an arithmetic number, because the mean of its divisors is an integer number (705938).

2^2117811 is an apocalyptic number.

2117811 is a deficient number, since it is larger than the sum of its proper divisors (705941).

2117811 is an equidigital number, since it uses as much as digits as its factorization.

2117811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705940.

The product of its digits is 112, while the sum is 21.

The square root of 2117811 is about 1455.2700780268. The cubic root of 2117811 is about 128.4189357852.

The spelling of 2117811 in words is "two million, one hundred seventeen thousand, eight hundred eleven".