2091840 has 56 divisors (see below), whose sum is σ = 6644640. Its totient is φ = 557568.

The previous prime is 2091839. The next prime is 2091847. The reversal of 2091840 is 481902.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nialpdrome in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 2091840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2091847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 130 + ... + 2049.

2^2091840 is an apocalyptic number.

2091840 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 2091840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3322320).

2091840 is an abundant number, since it is smaller than the sum of its proper divisors (4552800).

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

2091840 is a wasteful number, since it uses less digits than its factorization.

2091840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2199 (or 2189 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 2091840 is about 1446.3194667846. The cubic root of 2091840 is about 127.8918357066.

The spelling of 2091840 in words is "two million, ninety-one thousand, eight hundred forty".