521313840 has 160 divisors (see below), whose sum is σ = 1901396160. Its totient is φ = 130830336.

The previous prime is 521313839. The next prime is 521313853. The reversal of 521313840 is 48313125.

It is a happy number.

521313840 is a `hidden beast` number, since 521 + 3 + 138 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29622 + ... + 43818.

It is an arithmetic number, because the mean of its divisors is an integer number (11883726).

Almost surely, 2^521313840 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 521313840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (950698080).

521313840 is an abundant number, since it is smaller than the sum of its proper divisors (1380082320).

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

521313840 is a wasteful number, since it uses less digits than its factorization.

521313840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14236 (or 14224 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 521313840 is about 22832.2981760488. The cubic root of 521313840 is about 804.8218372999.

Adding to 521313840 its reverse (48313125), we get a palindrome (569626965).

The spelling of 521313840 in words is "five hundred twenty-one million, three hundred thirteen thousand, eight hundred forty".