501312640 has 64 divisors (see below), whose sum is σ = 1218192120. Its totient is φ = 197222400.

The previous prime is 501312631. The next prime is 501312649. The reversal of 501312640 is 46213105.

It is an interprime number because it is at equal distance from previous prime (501312631) and next prime (501312649).

It can be written as a sum of positive squares in 4 ways, for example, as 252682816 + 248629824 = 15896^2 + 15768^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (501312649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32620 + ... + 45460.

Almost surely, 2^501312640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 501312640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (609096060).

501312640 is an abundant number, since it is smaller than the sum of its proper divisors (716879480).

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

501312640 is a wasteful number, since it uses less digits than its factorization.

501312640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12921 (or 12909 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 501312640 is about 22390.0120589516. The cubic root of 501312640 is about 794.3944811014.

Adding to 501312640 its reverse (46213105), we get a palindrome (547525745).

The spelling of 501312640 in words is "five hundred one million, three hundred twelve thousand, six hundred forty".