53213521 has 8 divisors (see below), whose sum is σ = 55618920. Its totient is φ = 50846208.

The previous prime is 53213497. The next prime is 53213543. The reversal of 53213521 is 12531235.

It can be written as a sum of positive squares in 4 ways, for example, as 14288400 + 38925121 = 3780^2 + 6239^2 .

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 53213521 - 2⁷ = 53213393 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 53213492 and 53213501.

It is not an unprimeable number, because it can be changed into a prime (53213551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6646 + ... + 12271.

It is an arithmetic number, because the mean of its divisors is an integer number (6952365).

Almost surely, 2^53213521 is an apocalyptic number.

It is an amenable number.

53213521 is a deficient number, since it is larger than the sum of its proper divisors (2405399).

53213521 is a wasteful number, since it uses less digits than its factorization.

53213521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19043.

The product of its digits is 900, while the sum is 22.

The square root of 53213521 is about 7294.7598315503. The cubic root of 53213521 is about 376.1323309113.

Adding to 53213521 its reverse (12531235), we get a palindrome (65744756).

The spelling of 53213521 in words is "fifty-three million, two hundred thirteen thousand, five hundred twenty-one".