408394240 has 80 divisors (see below), whose sum is σ = 1013138280. Its totient is φ = 157696000.

The previous prime is 408394183. The next prime is 408394267. The reversal of 408394240 is 42493804.

It can be written as a sum of positive squares in 4 ways, for example, as 401922304 + 6471936 = 20048^2 + 2544^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 408394196 and 408394205.

It is an unprimeable number.

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, 71490 + ... + 76990.

Almost surely, 2^408394240 is an apocalyptic number.

408394240 is a gapful number since it is divisible by the number (40) 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 408394240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (506569140).

408394240 is an abundant number, since it is smaller than the sum of its proper divisors (604744040).

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

408394240 is an equidigital number, since it uses as much as digits as its factorization.

408394240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5553 (or 5537 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 408394240 is about 20208.7664146033. The cubic root of 408394240 is about 741.9247676937.

The spelling of 408394240 in words is "four hundred eight million, three hundred ninety-four thousand, two hundred forty".