1990980 has 60 divisors (see below), whose sum is σ = 6250860. Its totient is φ = 530496.

The previous prime is 1990973. The next prime is 1990981. The reversal of 1990980 is 890991.

It can be written as a sum of positive squares in 2 ways, for example, as 1498176 + 492804 = 1224^2 + 702^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1990981) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1006 + ... + 2234.

It is an arithmetic number, because the mean of its divisors is an integer number (104181).

2^1990980 is an apocalyptic number.

1990980 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 1990980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3125430).

1990980 is an abundant number, since it is smaller than the sum of its proper divisors (4259880).

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

1990980 is a wasteful number, since it uses less digits than its factorization.

1990980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1250 (or 1239 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The square root of 1990980 is about 1411.0209070032. The cubic root of 1990980 is about 125.8024113992.

The spelling of 1990980 in words is "one million, nine hundred ninety thousand, nine hundred eighty".