2191000 has 64 divisors (see below), whose sum is σ = 5878080. Its totient is φ = 748800.

The previous prime is 2190997. The next prime is 2191001. The reversal of 2191000 is 1912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6844 + ... + 7156.

It is an arithmetic number, because the mean of its divisors is an integer number (91845).

2^2191000 is an apocalyptic number.

2191000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2191000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2939040).

2191000 is an abundant number, since it is smaller than the sum of its proper divisors (3687080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2191000 is a wasteful number, since it uses less digits than its factorization.

2191000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341 (or 327 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 2191000 is about 1480.2026888234. The cubic root of 2191000 is about 129.8815489094.

Adding to 2191000 its reverse (1912), we get a palindrome (2192912).

The spelling of 2191000 in words is "two million, one hundred ninety-one thousand".