1968409 has 9 divisors (see below), whose sum is σ = 2091999.
Its totient is φ = 1851960.
The previous prime is 1968403. The next prime is 1968427. The reversal of 1968409 is 9048691.
The square root of 1968409 is 1403.
It is a perfect power (a square), and thus also a powerful number.
It can be written as a sum of positive squares in only one way, i.e., 64009 + 1904400 = 253^2 + 1380^2
It is not a de Polignac number, because 1968409 - 23 = 1968401 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (1968401) by changing a digit.
It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32239 + ... + 32299.
21968409 is an apocalyptic number.
1968409 is the 1403-rd square number.
1968409 is the 702-nd centered octagonal number.
It is an amenable number.
1968409 is a deficient number, since it is larger than the sum of its proper divisors (123590).
1968409 is an frugal number, since it uses more digits than its factorization.
1968409 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 168 (or 84 counting only the distinct ones).
The product of its (nonzero) digits is 15552, while the sum is 37.
The cubic root of 1968409 is about 125.3252118310.
The spelling of 1968409 in words is "one million, nine hundred sixty-eight thousand, four hundred nine".