65663813 has 2 divisors, whose sum is σ = 65663814. Its totient is φ = 65663812.

The previous prime is 65663783. The next prime is 65663821. The reversal of 65663813 is 31836656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60497284 + 5166529 = 7778^2 + 2273^2 .

It is a cyclic number.

It is not a de Polignac number, because 65663813 - 2⁶ = 65663749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65663893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32831906 + 32831907.

It is an arithmetic number, because the mean of its divisors is an integer number (32831907).

Almost surely, 2^65663813 is an apocalyptic number.

It is an amenable number.

65663813 is a deficient number, since it is larger than the sum of its proper divisors (1).

65663813 is an equidigital number, since it uses as much as digits as its factorization.

65663813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 38.

The square root of 65663813 is about 8103.3211092737. The cubic root of 65663813 is about 403.4366658419.

The spelling of 65663813 in words is "sixty-five million, six hundred sixty-three thousand, eight hundred thirteen".