521303345 has 8 divisors (see below), whose sum is σ = 625991976. Its totient is φ = 416757376.

The previous prime is 521303339. The next prime is 521303381. The reversal of 521303345 is 543303125.

It can be written as a sum of positive squares in 4 ways, for example, as 34527376 + 486775969 = 5876^2 + 22063^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 521303345 - 2⁸ = 521303089 is a prime.

It is a super-3 number, since 3×521303345³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27452 + ... + 42381.

It is an arithmetic number, because the mean of its divisors is an integer number (78248997).

Almost surely, 2^521303345 is an apocalyptic number.

It is an amenable number.

521303345 is a deficient number, since it is larger than the sum of its proper divisors (104688631).

521303345 is a wasteful number, since it uses less digits than its factorization.

521303345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71331.

The product of its (nonzero) digits is 5400, while the sum is 26.

The square root of 521303345 is about 22832.0683469545. The cubic root of 521303345 is about 804.8164364190.

The spelling of 521303345 in words is "five hundred twenty-one million, three hundred three thousand, three hundred forty-five".