1988440 has 16 divisors (see below), whose sum is σ = 4474080. Its totient is φ = 795360.

The previous prime is 1988423. The next prime is 1988453. The reversal of 1988440 is 448891.

1988440 = 345² + 346² + ... + 360².

It is a junction number, because it is equal to n+sod(n) for n = 1988396 and 1988405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24816 + ... + 24895.

It is an arithmetic number, because the mean of its divisors is an integer number (279630).

2^1988440 is an apocalyptic number.

1988440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1988440 is an abundant number, since it is smaller than the sum of its proper divisors (2485640).

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

1988440 is a wasteful number, since it uses less digits than its factorization.

1988440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49722 (or 49718 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 1988440 is about 1410.1205622215. The cubic root of 1988440 is about 125.7488910046.

The spelling of 1988440 in words is "one million, nine hundred eighty-eight thousand, four hundred forty".