1939840 has 64 divisors (see below), whose sum is σ = 5312160. Its totient is φ = 663552.

The previous prime is 1939837. The next prime is 1939841. The reversal of 1939840 is 489391.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 1939796 and 1939805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1939841) 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, 4264 + ... + 4696.

2^1939840 is an apocalyptic number.

1939840 is a gapful number since it is divisible by the number (10) 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 1939840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2656080).

1939840 is an abundant number, since it is smaller than the sum of its proper divisors (3372320).

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

1939840 is an equidigital number, since it uses as much as digits as its factorization.

1939840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 1939840 is about 1392.7813898814. The cubic root of 1939840 is about 124.7159416424.

The spelling of 1939840 in words is "one million, nine hundred thirty-nine thousand, eight hundred forty".