66649 has 8 divisors (see below), whose sum is σ = 74592. Its totient is φ = 59040.

The previous prime is 66643. The next prime is 66653. The reversal of 66649 is 94666.

66649 is nontrivially palindromic in base 6.

66649 is an esthetic number in base 6, because in such base its adjacent digits differ by 1.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66649 - 2⁵ = 66617 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 66649.

It is not an unprimeable number, because it can be changed into a prime (66643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 762 + ... + 844.

It is an arithmetic number, because the mean of its divisors is an integer number (9324).

2⁶⁶⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

66649 is a deficient number, since it is larger than the sum of its proper divisors (7943).

66649 is a wasteful number, since it uses less digits than its factorization.

66649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167.

The product of its digits is 7776, while the sum is 31.

The square root of 66649 is about 258.1646761275. The cubic root of 66649 is about 40.5444312462.

The spelling of 66649 in words is "sixty-six thousand, six hundred forty-nine".