53403521 has 2 divisors, whose sum is σ = 53403522. Its totient is φ = 53403520.

The previous prime is 53403517. The next prime is 53403523. The reversal of 53403521 is 12530435.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48497296 + 4906225 = 6964^2 + 2215^2 .

It is a cyclic number.

It is not a de Polignac number, because 53403521 - 2² = 53403517 is a prime.

Together with 53403523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (53403523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26701760 + 26701761.

It is an arithmetic number, because the mean of its divisors is an integer number (26701761).

Almost surely, 2^53403521 is an apocalyptic number.

It is an amenable number.

53403521 is a deficient number, since it is larger than the sum of its proper divisors (1).

53403521 is an equidigital number, since it uses as much as digits as its factorization.

53403521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 53403521 is about 7307.7712744721. The cubic root of 53403521 is about 376.5794619782.

Adding to 53403521 its reverse (12530435), we get a palindrome (65933956).

The spelling of 53403521 in words is "fifty-three million, four hundred three thousand, five hundred twenty-one".