521651328 has 192 divisors, whose sum is σ = 1551950400. Its totient is φ = 155105280.

The previous prime is 521651309. The next prime is 521651329. The reversal of 521651328 is 823156125.

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (521651329) 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 23 ways as a sum of consecutive naturals, for example, 4785738 + ... + 4785846.

It is an arithmetic number, because the mean of its divisors is an integer number (8083075).

Almost surely, 2^521651328 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 521651328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (775975200).

521651328 is an abundant number, since it is smaller than the sum of its proper divisors (1030299072).

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

521651328 is a wasteful number, since it uses less digits than its factorization.

521651328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251 (or 228 counting only the distinct ones).

The product of its digits is 14400, while the sum is 33.

The square root of 521651328 is about 22839.6875635373. The cubic root of 521651328 is about 804.9954749434.

The spelling of 521651328 in words is "five hundred twenty-one million, six hundred fifty-one thousand, three hundred twenty-eight".