1986840 has 48 divisors (see below), whose sum is σ = 6458400. Its totient is φ = 529728.

The previous prime is 1986839. The next prime is 1986869. The reversal of 1986840 is 486891.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 1986795 and 1986804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2400 + ... + 3119.

It is an arithmetic number, because the mean of its divisors is an integer number (134550).

2^1986840 is an apocalyptic number.

1986840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1986840 is an abundant number, since it is smaller than the sum of its proper divisors (4471560).

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

1986840 is a wasteful number, since it uses less digits than its factorization.

1986840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5536 (or 5529 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1986840 is about 1409.5531206734. The cubic root of 1986840 is about 125.7151539688.

The spelling of 1986840 in words is "one million, nine hundred eighty-six thousand, eight hundred forty".