66577 has 4 divisors (see below), whose sum is σ = 76096. Its totient is φ = 57060.

The previous prime is 66571. The next prime is 66587. The reversal of 66577 is 77566.

66577 is an esthetic number in base 6, because in such base its adjacent digits differ by 1.

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: 77566 = 2 ⋅38783.

It is a cyclic number.

It is not a de Polignac number, because 66577 - 2³ = 66569 is a prime.

It is a Duffinian number.

66577 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (66571) 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, 4749 + ... + 4762.

It is an arithmetic number, because the mean of its divisors is an integer number (19024).

2⁶⁶⁵⁷⁷ is an apocalyptic number.

It is an amenable number.

66577 is a deficient number, since it is larger than the sum of its proper divisors (9519).

66577 is an equidigital number, since it uses as much as digits as its factorization.

66577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9518.

The product of its digits is 8820, while the sum is 31.

The square root of 66577 is about 258.0251925685. The cubic root of 66577 is about 40.5298261215.

The spelling of 66577 in words is "sixty-six thousand, five hundred seventy-seven".