65161550989 has 4 divisors (see below), whose sum is σ = 65521559740. Its totient is φ = 64801542240.

The previous prime is 65161550959. The next prime is 65161551017. The reversal of 65161550989 is 98905516156.

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 24232214889 + 40929336100 = 155667^2 + 202310^2 .

It is a cyclic number.

It is not a de Polignac number, because 65161550989 - 2¹⁵ = 65161518221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65161550939) 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, 180004104 + ... + 180004465.

It is an arithmetic number, because the mean of its divisors is an integer number (16380389935).

Almost surely, 2^65161550989 is an apocalyptic number.

It is an amenable number.

65161550989 is a deficient number, since it is larger than the sum of its proper divisors (360008751).

65161550989 is a wasteful number, since it uses less digits than its factorization.

65161550989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360008750.

The product of its (nonzero) digits is 2916000, while the sum is 55.

The spelling of 65161550989 in words is "sixty-five billion, one hundred sixty-one million, five hundred fifty thousand, nine hundred eighty-nine".