2191217 has 4 divisors (see below), whose sum is σ = 2504256. Its totient is φ = 1878180.

The previous prime is 2191199. The next prime is 2191229. The reversal of 2191217 is 7121912.

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 2191217 - 2¹⁰ = 2190193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2191192 and 2191201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191247) 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, 156509 + ... + 156522.

It is an arithmetic number, because the mean of its divisors is an integer number (626064).

2^2191217 is an apocalyptic number.

It is an amenable number.

2191217 is a deficient number, since it is larger than the sum of its proper divisors (313039).

2191217 is an equidigital number, since it uses as much as digits as its factorization.

2191217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313038.

The product of its digits is 252, while the sum is 23.

The square root of 2191217 is about 1480.2759877807. The cubic root of 2191217 is about 129.8858366571.

The spelling of 2191217 in words is "two million, one hundred ninety-one thousand, two hundred seventeen".