53121321 has 48 divisors (see below), whose sum is σ = 91054080. Its totient is φ = 29484000.

The previous prime is 53121319. The next prime is 53121337. The reversal of 53121321 is 12312135.

53121321 is a `hidden beast` number, since 531 + 2 + 132 + 1 = 666.

It is not a de Polignac number, because 53121321 - 2¹ = 53121319 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 53121294 and 53121303.

It is not an unprimeable number, because it can be changed into a prime (53121361) 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 47 ways as a sum of consecutive naturals, for example, 57856 + ... + 58766.

It is an arithmetic number, because the mean of its divisors is an integer number (1896960).

Almost surely, 2^53121321 is an apocalyptic number.

It is an amenable number.

53121321 is a deficient number, since it is larger than the sum of its proper divisors (37932759).

53121321 is a wasteful number, since it uses less digits than its factorization.

53121321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978 (or 975 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 53121321 is about 7288.4374868692. The cubic root of 53121321 is about 375.9149710589.

Adding to 53121321 its reverse (12312135), we get a palindrome (65433456).

The spelling of 53121321 in words is "fifty-three million, one hundred twenty-one thousand, three hundred twenty-one".