2191697 has 4 divisors (see below), whose sum is σ = 2219520. Its totient is φ = 2163876.

The previous prime is 2191687. The next prime is 2191703. The reversal of 2191697 is 7961912.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2191697 - 2⁶ = 2191633 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191627) 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, 13793 + ... + 13950.

It is an arithmetic number, because the mean of its divisors is an integer number (554880).

2^2191697 is an apocalyptic number.

It is an amenable number.

2191697 is a deficient number, since it is larger than the sum of its proper divisors (27823).

2191697 is an equidigital number, since it uses as much as digits as its factorization.

2191697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27822.

The product of its digits is 6804, while the sum is 35.

The square root of 2191697 is about 1480.4381108307. The cubic root of 2191697 is about 129.8953200704.

The spelling of 2191697 in words is "two million, one hundred ninety-one thousand, six hundred ninety-seven".