65918161 has 9 divisors (see below), whose sum is σ = 69104539. Its totient is φ = 62873536.

The previous prime is 65918159. The next prime is 65918173. The reversal of 65918161 is 16181956.

The square root of 65918161 is 8119.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 26780625 + 39137536 = 5175^2 + 6256^2 .

It is not a de Polignac number, because 65918161 - 2¹ = 65918159 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65918161.

It is not an unprimeable number, because it can be changed into a prime (65918141) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 186561 + ... + 186913.

Almost surely, 2^65918161 is an apocalyptic number.

65918161 is the 8119-th square number.

65918161 is the 4060-th centered octagonal number.

It is an amenable number.

65918161 is a deficient number, since it is larger than the sum of its proper divisors (3186378).

65918161 is an frugal number, since it uses more digits than its factorization.

65918161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 752 (or 376 counting only the distinct ones).

The product of its digits is 12960, while the sum is 37.

The cubic root of 65918161 is about 403.9568970941.

The spelling of 65918161 in words is "sixty-five million, nine hundred eighteen thousand, one hundred sixty-one".