1990440 has 128 divisors (see below), whose sum is σ = 7056000. Its totient is φ = 497664.

The previous prime is 1990433. The next prime is 1990441. The reversal of 1990440 is 440991.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20472 + ... + 20568.

It is an arithmetic number, because the mean of its divisors is an integer number (55125).

2^1990440 is an apocalyptic number.

1990440 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 1990440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3528000).

1990440 is an abundant number, since it is smaller than the sum of its proper divisors (5065560).

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

1990440 is a wasteful number, since it uses less digits than its factorization.

1990440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1990440 is about 1410.8295432121. The cubic root of 1990440 is about 125.7910368592.

The spelling of 1990440 in words is "one million, nine hundred ninety thousand, four hundred forty".