2191365 has 48 divisors (see below), whose sum is σ = 4380480. Its totient is φ = 1002240.

The previous prime is 2191363. The next prime is 2191373. The reversal of 2191365 is 5631912.

It is not a de Polignac number, because 2191365 - 2¹ = 2191363 is a prime.

It is a super-3 number, since 3×2191365³ = 31569333820294656375, which contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9289 + ... + 9521.

It is an arithmetic number, because the mean of its divisors is an integer number (91260).

2^2191365 is an apocalyptic number.

2191365 is the 855-th octagonal number.

It is an amenable number.

2191365 is a deficient number, since it is larger than the sum of its proper divisors (2189115).

2191365 is a wasteful number, since it uses less digits than its factorization.

2191365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 271 counting only the distinct ones).

The product of its digits is 1620, while the sum is 27.

The square root of 2191365 is about 1480.3259776144. The cubic root of 2191365 is about 129.8887608572. Note that the first 3 decimals are identical.

It can be divided in two parts, 2191 and 365, that added together give a triangular number (2556 = T₇₁).

The spelling of 2191365 in words is "two million, one hundred ninety-one thousand, three hundred sixty-five".