1984990 has 24 divisors (see below), whose sum is σ = 4157352. Its totient is φ = 680400.

The previous prime is 1984981. The next prime is 1984991. The reversal of 1984990 is 994891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1984991) 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 11 ways as a sum of consecutive naturals, for example, 1536 + ... + 2515.

It is an arithmetic number, because the mean of its divisors is an integer number (173223).

2^1984990 is an apocalyptic number.

1984990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1984990 is an abundant number, since it is smaller than the sum of its proper divisors (2172362).

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

1984990 is a wasteful number, since it uses less digits than its factorization.

1984990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4072 (or 4065 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 1984990 is about 1408.8967314889. The cubic root of 1984990 is about 125.6761229351.

Subtracting from 1984990 its reverse (994891), we obtain a palindrome (990099).

The spelling of 1984990 in words is "one million, nine hundred eighty-four thousand, nine hundred ninety".