64681 has 4 divisors (see below), whose sum is σ = 65664. Its totient is φ = 63700.

The previous prime is 64679. The next prime is 64693. The reversal of 64681 is 18646.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18646 = 2 ⋅9323.

It is a cyclic number.

It is not a de Polignac number, because 64681 - 2¹ = 64679 is a prime.

It is a super-2 number, since 2×64681² = 8367263522, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (64601) 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, 385 + ... + 526.

It is an arithmetic number, because the mean of its divisors is an integer number (16416).

2⁶⁴⁶⁸¹ is an apocalyptic number.

It is an amenable number.

64681 is a deficient number, since it is larger than the sum of its proper divisors (983).

64681 is an equidigital number, since it uses as much as digits as its factorization.

64681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982.

The product of its digits is 1152, while the sum is 25.

The square root of 64681 is about 254.3245957433. The cubic root of 64681 is about 40.1413747409.

It can be divided in two parts, 646 and 81, that multiplied together give a triangular number (52326 = T₃₂₃).

The spelling of 64681 in words is "sixty-four thousand, six hundred eighty-one".