65551 has 2 divisors, whose sum is σ = 65552.
Its totient is φ = 65550.
The previous prime is 65543. The next prime is 65557. The reversal of 65551 is 15556.
It can be divided in two parts, 6555 and 1, that added together give a palindrome (6556).
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 65551 - 23 = 65543 is a prime.
It is a Chen prime.
65551 is a lucky number.
It is a nialpdrome in base 10.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (65557) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (5) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32775 + 32776.
It is an arithmetic number, because the mean of its divisors is an integer number (32776).
265551 is an apocalyptic number.
65551 is the 115-th centered decagonal number.
65551 is a deficient number, since it is larger than the sum of its proper divisors (1).
65551 is an equidigital number, since it uses as much as digits as its factorization.
65551 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 750, while the sum is 22.
The square root of 65551 is about 256.0292951988.
The cubic root of 65551 is about 40.3205493411.
The spelling of 65551 in words is "sixty-five thousand, five hundred fifty-one".