65643257 has 2 divisors, whose sum is σ = 65643258. Its totient is φ = 65643256.

The previous prime is 65643229. The next prime is 65643283. The reversal of 65643257 is 75234656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50751376 + 14891881 = 7124^2 + 3859^2 .

It is a cyclic number.

It is not a de Polignac number, because 65643257 - 2²⁰ = 64594681 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 65643257.

It is not a weakly prime, because it can be changed into another prime (65645257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32821628 + 32821629.

It is an arithmetic number, because the mean of its divisors is an integer number (32821629).

Almost surely, 2^65643257 is an apocalyptic number.

It is an amenable number.

65643257 is a deficient number, since it is larger than the sum of its proper divisors (1).

65643257 is an equidigital number, since it uses as much as digits as its factorization.

65643257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 38.

The square root of 65643257 is about 8102.0526411521. The cubic root of 65643257 is about 403.3945629482.

The spelling of 65643257 in words is "sixty-five million, six hundred forty-three thousand, two hundred fifty-seven".