65420521 has 2 divisors, whose sum is σ = 65420522. Its totient is φ = 65420520.

The previous prime is 65420513. The next prime is 65420527. The reversal of 65420521 is 12502456.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54922921 + 10497600 = 7411^2 + 3240^2 .

It is a cyclic number.

It is not a de Polignac number, because 65420521 - 2³ = 65420513 is a prime.

It is a super-2 number, since 2×65420521² = 8559689135822882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (65420527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32710260 + 32710261.

It is an arithmetic number, because the mean of its divisors is an integer number (32710261).

Almost surely, 2^65420521 is an apocalyptic number.

It is an amenable number.

65420521 is a deficient number, since it is larger than the sum of its proper divisors (1).

65420521 is an equidigital number, since it uses as much as digits as its factorization.

65420521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 65420521 is about 8088.2953086544. The cubic root of 65420521 is about 402.9377894107.

Adding to 65420521 its reverse (12502456), we get a palindrome (77922977).

The spelling of 65420521 in words is "sixty-five million, four hundred twenty thousand, five hundred twenty-one".