64881 has 14 divisors (see below), whose sum is σ = 98370. Its totient is φ = 42768.
The previous prime is 64879. The next prime is 64891. The reversal of 64881 is 18846.
It can be written as a sum of positive squares in only one way, i.e., 46656 + 18225 = 216^2 + 135^2 .
It is not a de Polignac number, because 64881 - 21 = 64879 is a prime.
It is a super-2 number, since 2×648812 = 8419088322, which contains 22 as substring.
It is a Harshad number since it is a multiple of its sum of digits (27).
It is a Curzon number.
64881 is a lucky number.
It is a plaindrome in base 13.
It is a nialpdrome in base 16.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 64881.
It is not an unprimeable number, because it can be changed into a prime (64811) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (11) of ones.
It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 685 + ... + 773.
264881 is an apocalyptic number.
It is an amenable number.
64881 is a deficient number, since it is larger than the sum of its proper divisors (33489).
64881 is an frugal number, since it uses more digits than its factorization.
64881 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 107 (or 92 counting only the distinct ones).
The product of its digits is 1536, while the sum is 27.
The square root of 64881 is about 254.7174905655. The cubic root of 64881 is about 40.1827058603.
It can be divided in two parts, 648 and 81, that added together give a 6-th power (729 = 36).
The spelling of 64881 in words is "sixty-four thousand, eight hundred eighty-one".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.001 sec. • engine limits •