1822640 has 20 divisors (see below), whose sum is σ = 4237824. Its totient is φ = 729024.

The previous prime is 1822637. The next prime is 1822649. The reversal of 1822640 is 462281.

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (1822649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11312 + ... + 11471.

2^1822640 is an apocalyptic number.

1822640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1822640 is an abundant number, since it is smaller than the sum of its proper divisors (2415184).

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

1822640 is a wasteful number, since it uses less digits than its factorization.

1822640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22796 (or 22790 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 1822640 is about 1350.0518508561. The cubic root of 1822640 is about 122.1519203907.

The spelling of 1822640 in words is "one million, eight hundred twenty-two thousand, six hundred forty".