403640640 has 168 divisors, whose sum is σ = 1495290888. Its totient is φ = 99348480.

The previous prime is 403640621. The next prime is 403640651. The reversal of 403640640 is 46046304.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 112896 + 403527744 = 336^2 + 20088^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32050 + ... + 42830.

It is an arithmetic number, because the mean of its divisors is an integer number (8900541).

Almost surely, 2^403640640 is an apocalyptic number.

403640640 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 403640640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747645444).

403640640 is an abundant number, since it is smaller than the sum of its proper divisors (1091650248).

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

403640640 is a wasteful number, since it uses less digits than its factorization.

403640640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10817 (or 10804 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 403640640 is about 20090.8098393270. The cubic root of 403640640 is about 739.0349240650.

Adding to 403640640 its reverse (46046304), we get a palindrome (449686944).

The spelling of 403640640 in words is "four hundred three million, six hundred forty thousand, six hundred forty".