65881 has 2 divisors, whose sum is σ = 65882.
Its totient is φ = 65880.
The previous prime is 65867. The next prime is 65899. The reversal of 65881 is 18856.
It is a happy number.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 57600 + 8281 = 240^2 + 91^2
It is a cyclic number.
It is not a de Polignac number, because 65881 - 213 = 57689 is a prime.
It is a super-2 number, since 2×658812 = 8680612322, which contains 22 as substring.
It is a Chen prime.
65881 is a lucky number.
It is not a weakly prime, because it can be changed into another prime (65831) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32940 + 32941.
It is an arithmetic number, because the mean of its divisors is an integer number (32941).
265881 is an apocalyptic number.
It is an amenable number.
65881 is a deficient number, since it is larger than the sum of its proper divisors (1).
65881 is an equidigital number, since it uses as much as digits as its factorization.
65881 is an evil number, because the sum of its binary digits is even.
The product of its digits is 1920, while the sum is 28.
The square root of 65881 is about 256.6729436462.
The cubic root of 65881 is about 40.3880973334.
It can be divided in two parts, 65 and 881, that added together give a triangular number (946 = T43).
The spelling of 65881 in words is "sixty-five thousand, eight hundred eighty-one".