65563681 has 2 divisors, whose sum is σ = 65563682. Its totient is φ = 65563680.

The previous prime is 65563669. The next prime is 65563697. The reversal of 65563681 is 18636556.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59536656 + 6027025 = 7716^2 + 2455^2 .

It is a cyclic number.

It is not a de Polignac number, because 65563681 - 2⁵ = 65563649 is a prime.

It is a super-2 number, since 2×65563681² = 8597192532539522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (65563621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32781840 + 32781841.

It is an arithmetic number, because the mean of its divisors is an integer number (32781841).

Almost surely, 2^65563681 is an apocalyptic number.

It is an amenable number.

65563681 is a deficient number, since it is larger than the sum of its proper divisors (1).

65563681 is an equidigital number, since it uses as much as digits as its factorization.

65563681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 40.

The square root of 65563681 is about 8097.1402976607. The cubic root of 65563681 is about 403.2314920950.

The spelling of 65563681 in words is "sixty-five million, five hundred sixty-three thousand, six hundred eighty-one".