2191406 has 16 divisors (see below), whose sum is σ = 3784416. Its totient is φ = 932256.

The previous prime is 2191393. The next prime is 2191429. The reversal of 2191406 is 6041912.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1700 + ... + 2696.

It is an arithmetic number, because the mean of its divisors is an integer number (236526).

2^2191406 is an apocalyptic number.

2191406 is a deficient number, since it is larger than the sum of its proper divisors (1593010).

2191406 is a wasteful number, since it uses less digits than its factorization.

2191406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 2191406 is about 1480.3398258508. The cubic root of 2191406 is about 129.8895709164.

The spelling of 2191406 in words is "two million, one hundred ninety-one thousand, four hundred six".