1990040 has 64 divisors (see below), whose sum is σ = 4989600. Its totient is φ = 709632.

The previous prime is 1990039. The next prime is 1990069. The reversal of 1990040 is 400991.

It is a junction number, because it is equal to n+sod(n) for n = 1989988 and 1990015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22316 + ... + 22404.

2^1990040 is an apocalyptic number.

1990040 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 1990040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2494800).

1990040 is an abundant number, since it is smaller than the sum of its proper divisors (2999560).

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

1990040 is a wasteful number, since it uses less digits than its factorization.

1990040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 1990040 is about 1410.6877755194. The cubic root of 1990040 is about 125.7826099476.

The spelling of 1990040 in words is "one million, nine hundred ninety thousand, forty".