520749840 has 240 divisors, whose sum is σ = 1800474048. Its totient is φ = 124360704.

The previous prime is 520749833. The next prime is 520749937. The reversal of 520749840 is 48947025.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1500547 + ... + 1500893.

Almost surely, 2^520749840 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 520749840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (900237024).

520749840 is an abundant number, since it is smaller than the sum of its proper divisors (1279724208).

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

520749840 is a wasteful number, since it uses less digits than its factorization.

520749840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 426 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 520749840 is about 22819.9439087829. The cubic root of 520749840 is about 804.5314918460.

The spelling of 520749840 in words is "five hundred twenty million, seven hundred forty-nine thousand, eight hundred forty".