65365721 has 2 divisors, whose sum is σ = 65365722. Its totient is φ = 65365720.

The previous prime is 65365711. The next prime is 65365753. The reversal of 65365721 is 12756356.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38440000 + 26925721 = 6200^2 + 5189^2 .

It is a cyclic number.

It is not a de Polignac number, because 65365721 - 2¹⁰ = 65364697 is a prime.

It is not a weakly prime, because it can be changed into another prime (65365711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32682860 + 32682861.

It is an arithmetic number, because the mean of its divisors is an integer number (32682861).

Almost surely, 2^65365721 is an apocalyptic number.

It is an amenable number.

65365721 is a deficient number, since it is larger than the sum of its proper divisors (1).

65365721 is an equidigital number, since it uses as much as digits as its factorization.

65365721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37800, while the sum is 35.

The square root of 65365721 is about 8084.9069877148. The cubic root of 65365721 is about 402.8252500075.

The spelling of 65365721 in words is "sixty-five million, three hundred sixty-five thousand, seven hundred twenty-one".