2117591 has 4 divisors (see below), whose sum is σ = 2420112. Its totient is φ = 1815072.

The previous prime is 2117581. The next prime is 2117593. The reversal of 2117591 is 1957112.

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

It is not a de Polignac number, because 2117591 - 2¹⁴ = 2101207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2117591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2117593) 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, 151250 + ... + 151263.

It is an arithmetic number, because the mean of its divisors is an integer number (605028).

2^2117591 is an apocalyptic number.

2117591 is a deficient number, since it is larger than the sum of its proper divisors (302521).

2117591 is an equidigital number, since it uses as much as digits as its factorization.

2117591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302520.

The product of its digits is 630, while the sum is 26.

The square root of 2117591 is about 1455.1944887196. The cubic root of 2117591 is about 128.4144888752.

The spelling of 2117591 in words is "two million, one hundred seventeen thousand, five hundred ninety-one".