509744640 has 80 divisors (see below), whose sum is σ = 1629614448. Its totient is φ = 135929856.

The previous prime is 509744593. The next prime is 509744647. The reversal of 509744640 is 46447905.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (509744647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25507 + ... + 40866.

Almost surely, 2^509744640 is an apocalyptic number.

It is an amenable number.

509744640 is an abundant number, since it is smaller than the sum of its proper divisors (1119869808).

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

509744640 is an equidigital number, since it uses as much as digits as its factorization.

509744640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66399 (or 66383 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 39.

The square root of 509744640 is about 22577.5251079475. The cubic root of 509744640 is about 798.8236042977.

The spelling of 509744640 in words is "five hundred nine million, seven hundred forty-four thousand, six hundred forty".