520129321 has 4 divisors (see below), whose sum is σ = 532815444. Its totient is φ = 507443200.

The previous prime is 520129301. The next prime is 520129369. The reversal of 520129321 is 123921025.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 297045225 + 223084096 = 17235^2 + 14936^2 .

It is a cyclic number.

It is not a de Polignac number, because 520129321 - 2⁵ = 520129289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (520129301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6343000 + ... + 6343081.

It is an arithmetic number, because the mean of its divisors is an integer number (133203861).

Almost surely, 2^520129321 is an apocalyptic number.

It is an amenable number.

520129321 is a deficient number, since it is larger than the sum of its proper divisors (12686123).

520129321 is a wasteful number, since it uses less digits than its factorization.

520129321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12686122.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 520129321 is about 22806.3438762113. The cubic root of 520129321 is about 804.2118082791.

The spelling of 520129321 in words is "five hundred twenty million, one hundred twenty-nine thousand, three hundred twenty-one".