65121140253665 has 4 divisors (see below), whose sum is σ = 78145368304404. Its totient is φ = 52096912202928.

The previous prime is 65121140253643. The next prime is 65121140253703. The reversal of 65121140253665 is 56635204112156.

It is a happy number.

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 40374485144464 + 24746655109201 = 6354092^2 + 4974601^2 .

It is a cyclic number.

It is not a de Polignac number, because 65121140253665 - 2²² = 65121136059361 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6512114025362 + ... + 6512114025371.

It is an arithmetic number, because the mean of its divisors is an integer number (19536342076101).

Almost surely, 2^{65121140253665} is an apocalyptic number.

It is an amenable number.

65121140253665 is a deficient number, since it is larger than the sum of its proper divisors (13024228050739).

65121140253665 is a wasteful number, since it uses less digits than its factorization.

65121140253665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13024228050738.

The product of its (nonzero) digits is 1296000, while the sum is 47.

The spelling of 65121140253665 in words is "sixty-five trillion, one hundred twenty-one billion, one hundred forty million, two hundred fifty-three thousand, six hundred sixty-five".