65381609 has 4 divisors (see below), whose sum is σ = 69227604. Its totient is φ = 61535616.

The previous prime is 65381581. The next prime is 65381611. The reversal of 65381609 is 90618356.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33965584 + 31416025 = 5828^2 + 5605^2 .

It is a cyclic number.

It is not a de Polignac number, because 65381609 - 2⁸ = 65381353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (65381509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1922972 + ... + 1923005.

It is an arithmetic number, because the mean of its divisors is an integer number (17306901).

Almost surely, 2^65381609 is an apocalyptic number.

It is an amenable number.

65381609 is a deficient number, since it is larger than the sum of its proper divisors (3845995).

65381609 is a wasteful number, since it uses less digits than its factorization.

65381609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3845994.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 65381609 is about 8085.8894996160. The cubic root of 65381609 is about 402.8578846923.

The spelling of 65381609 in words is "sixty-five million, three hundred eighty-one thousand, six hundred nine".