513620640 has 144 divisors (see below), whose sum is σ = 1887624648. Its totient is φ = 126425088.

The previous prime is 513620629. The next prime is 513620641. The reversal of 513620640 is 46026315.

513620640 is a `hidden beast` number, since 5 + 13 + 6 + 2 + 0 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 328769424 + 184851216 = 18132^2 + 13596^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (513620641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5002 + ... + 32438.

Almost surely, 2^513620640 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 513620640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (943812324).

513620640 is an abundant number, since it is smaller than the sum of its proper divisors (1374004008).

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

513620640 is a wasteful number, since it uses less digits than its factorization.

513620640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27471 (or 27460 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 513620640 is about 22663.2001270783. The cubic root of 513620640 is about 800.8431943003.

Adding to 513620640 its reverse (46026315), we get a palindrome (559646955).

The spelling of 513620640 in words is "five hundred thirteen million, six hundred twenty thousand, six hundred forty".