65638249 has 2 divisors, whose sum is σ = 65638250. Its totient is φ = 65638248.

The previous prime is 65638247. The next prime is 65638277. The reversal of 65638249 is 94283656.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55398249 + 10240000 = 7443^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 65638249 - 2¹ = 65638247 is a prime.

Together with 65638247, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (65638247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32819124 + 32819125.

It is an arithmetic number, because the mean of its divisors is an integer number (32819125).

Almost surely, 2^65638249 is an apocalyptic number.

It is an amenable number.

65638249 is a deficient number, since it is larger than the sum of its proper divisors (1).

65638249 is an equidigital number, since it uses as much as digits as its factorization.

65638249 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 43.

The square root of 65638249 is about 8101.7435777739. The cubic root of 65638249 is about 403.3843042080.

The spelling of 65638249 in words is "sixty-five million, six hundred thirty-eight thousand, two hundred forty-nine".