1943990 has 16 divisors (see below), whose sum is σ = 3548448. Its totient is φ = 766656.

The previous prime is 1943959. The next prime is 1943993. The reversal of 1943990 is 993491.

It is a self number, because there is not a number n which added to its sum of digits gives 1943990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1943993) 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 7 ways as a sum of consecutive naturals, for example, 602 + ... + 2061.

It is an arithmetic number, because the mean of its divisors is an integer number (221778).

2^1943990 is an apocalyptic number.

1943990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1943990 is a deficient number, since it is larger than the sum of its proper divisors (1604458).

1943990 is a wasteful number, since it uses less digits than its factorization.

1943990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2743.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 1943990 is about 1394.2704185344. The cubic root of 1943990 is about 124.8048153824.

The spelling of 1943990 in words is "one million, nine hundred forty-three thousand, nine hundred ninety".