1678240 has 48 divisors (see below), whose sum is σ = 4204872. Its totient is φ = 630784.

The previous prime is 1678231. The next prime is 1678249. The reversal of 1678240 is 428761.

It is an interprime number because it is at equal distance from previous prime (1678231) and next prime (1678249).

It can be written as a sum of positive squares in 4 ways, for example, as 1106704 + 571536 = 1052^2 + 756^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1678199 and 1678208.

It is not an unprimeable number, because it can be changed into a prime (1678249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2412 + ... + 3028.

2^1678240 is an apocalyptic number.

1678240 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 1678240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2102436).

1678240 is an abundant number, since it is smaller than the sum of its proper divisors (2526632).

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

1678240 is a wasteful number, since it uses less digits than its factorization.

1678240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649 (or 641 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 1678240 is about 1295.4690270323. The cubic root of 1678240 is about 118.8369114445.

The spelling of 1678240 in words is "one million, six hundred seventy-eight thousand, two hundred forty".