2191440 has 80 divisors (see below), whose sum is σ = 7106688. Its totient is φ = 557568.

The previous prime is 2191433. The next prime is 2191451. The reversal of 2191440 is 441912.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 5322 + ... + 5718.

2^2191440 is an apocalyptic number.

2191440 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 2191440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3553344).

2191440 is an abundant number, since it is smaller than the sum of its proper divisors (4915248).

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

2191440 is a wasteful number, since it uses less digits than its factorization.

2191440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436 (or 430 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 2191440 is about 1480.3513096559. The cubic root of 2191440 is about 129.8902426651.

The spelling of 2191440 in words is "two million, one hundred ninety-one thousand, four hundred forty".