1983990 has 32 divisors (see below), whose sum is σ = 4880736. Its totient is φ = 515840.

The previous prime is 1983979. The next prime is 1983997. The reversal of 1983990 is 993891.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1983997) 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 15 ways as a sum of consecutive naturals, for example, 424 + ... + 2036.

It is an arithmetic number, because the mean of its divisors is an integer number (152523).

2^1983990 is an apocalyptic number.

1983990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1983990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2440368).

1983990 is an abundant number, since it is smaller than the sum of its proper divisors (2896746).

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

1983990 is a wasteful number, since it uses less digits than its factorization.

1983990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1664.

The product of its (nonzero) digits is 17496, while the sum is 39.

The square root of 1983990 is about 1408.5417991668. The cubic root of 1983990 is about 125.6550149810.

Subtracting from 1983990 its reverse (993891), we obtain a palindrome (990099).

The spelling of 1983990 in words is "one million, nine hundred eighty-three thousand, nine hundred ninety".