65415521 has 2 divisors, whose sum is σ = 65415522. Its totient is φ = 65415520.

The previous prime is 65415509. The next prime is 65415527. The reversal of 65415521 is 12551456.

It is a happy number.

65415521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37957921 + 27457600 = 6161^2 + 5240^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65415521 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (65415527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32707760 + 32707761.

It is an arithmetic number, because the mean of its divisors is an integer number (32707761).

Almost surely, 2^65415521 is an apocalyptic number.

It is an amenable number.

65415521 is a deficient number, since it is larger than the sum of its proper divisors (1).

65415521 is an equidigital number, since it uses as much as digits as its factorization.

65415521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6000, while the sum is 29.

The square root of 65415521 is about 8087.9862141327. The cubic root of 65415521 is about 402.9275238231.

Adding to 65415521 its reverse (12551456), we get a palindrome (77966977).

The spelling of 65415521 in words is "sixty-five million, four hundred fifteen thousand, five hundred twenty-one".