52720321 has 4 divisors (see below), whose sum is σ = 52808644. Its totient is φ = 52632000.

The previous prime is 52720313. The next prime is 52720361. The reversal of 52720321 is 12302725.

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 30958096 + 21762225 = 5564^2 + 4665^2 .

It is a cyclic number.

It is not a de Polignac number, because 52720321 - 2³ = 52720313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 52720292 and 52720301.

It is not an unprimeable number, because it can be changed into a prime (52720361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43260 + ... + 44461.

It is an arithmetic number, because the mean of its divisors is an integer number (13202161).

Almost surely, 2^52720321 is an apocalyptic number.

It is an amenable number.

52720321 is a deficient number, since it is larger than the sum of its proper divisors (88323).

52720321 is an equidigital number, since it uses as much as digits as its factorization.

52720321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88322.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 52720321 is about 7260.8760490729. The cubic root of 52720321 is about 374.9666838550.

The spelling of 52720321 in words is "fifty-two million, seven hundred twenty thousand, three hundred twenty-one".