403640320 has 52 divisors (see below), whose sum is σ = 968667660. Its totient is φ = 161447936.

The previous prime is 403640261. The next prime is 403640329. The reversal of 403640320 is 23046304.

It can be written as a sum of positive squares in 2 ways, for example, as 175509504 + 228130816 = 13248^2 + 15104^2 .

It is a junction number, because it is equal to n+sod(n) for n = 403640291 and 403640300.

It is not an unprimeable number, because it can be changed into a prime (403640329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10626 + ... + 30334.

Almost surely, 2^403640320 is an apocalyptic number.

403640320 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 403640320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (484333830).

403640320 is an abundant number, since it is smaller than the sum of its proper divisors (565027340).

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

403640320 is an equidigital number, since it uses as much as digits as its factorization.

403640320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19738 (or 19716 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 403640320 is about 20090.8018754852. The cubic root of 403640320 is about 739.0347287665.

Adding to 403640320 its reverse (23046304), we get a palindrome (426686624).

The spelling of 403640320 in words is "four hundred three million, six hundred forty thousand, three hundred twenty".