404257840 has 120 divisors (see below), whose sum is σ = 1100233152. Its totient is φ = 137733120.

The previous prime is 404257831. The next prime is 404257873. The reversal of 404257840 is 48752404.

It is a happy number.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 404257796 and 404257805.

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 23 ways as a sum of consecutive naturals, for example, 1101337 + ... + 1101703.

Almost surely, 2^404257840 is an apocalyptic number.

404257840 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 404257840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (550116576).

404257840 is an abundant number, since it is smaller than the sum of its proper divisors (695975312).

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

404257840 is a wasteful number, since it uses less digits than its factorization.

404257840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 675 (or 662 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 34.

The square root of 404257840 is about 20106.1642289125. The cubic root of 404257840 is about 739.4114141234.

The spelling of 404257840 in words is "four hundred four million, two hundred fifty-seven thousand, eight hundred forty".