It is a Jordan-Polya number, since it can be written as 6! ⋅ (3!)4 ⋅ 2!.
It is a nialpdrome in base 12.
21866240 is an apocalyptic number.
1866240 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 1866240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3354417).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
1866240 is an frugal number, since it uses more digits than its factorization.
1866240 is an evil number, because the sum of its binary digits is even.
The square root of 1866240 is about 1366.1039491927. The cubic root of 1866240 is about 123.1182681607.
The spelling of 1866240 in words is "one million, eight hundred sixty-six thousand, two hundred forty".