1988840 has 32 divisors (see below), whose sum is σ = 5114880. Its totient is φ = 681792.

The previous prime is 1988839. The next prime is 1988843. The reversal of 1988840 is 488891.

It is a junction number, because it is equal to n+sod(n) for n = 1988794 and 1988803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1988843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3272 + ... + 3831.

It is an arithmetic number, because the mean of its divisors is an integer number (159840).

2^1988840 is an apocalyptic number.

1988840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1988840 is an abundant number, since it is smaller than the sum of its proper divisors (3126040).

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

1988840 is a wasteful number, since it uses less digits than its factorization.

1988840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7121 (or 7117 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 38.

The square root of 1988840 is about 1410.2623869337. The cubic root of 1988840 is about 125.7573224356.

The spelling of 1988840 in words is "one million, nine hundred eighty-eight thousand, eight hundred forty".