66557 has 8 divisors (see below), whose sum is σ = 72960. Its totient is φ = 60480.

The previous prime is 66553. The next prime is 66569. The reversal of 66557 is 75566.

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 66557 - 2² = 66553 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 66557.

It is not an unprimeable number, because it can be changed into a prime (66553) 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, 533 + ... + 645.

It is an arithmetic number, because the mean of its divisors is an integer number (9120).

2⁶⁶⁵⁵⁷ is an apocalyptic number.

It is an amenable number.

66557 is a deficient number, since it is larger than the sum of its proper divisors (6403).

66557 is a wasteful number, since it uses less digits than its factorization.

66557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163.

The product of its digits is 6300, while the sum is 29.

The square root of 66557 is about 257.9864337519. The cubic root of 66557 is about 40.5257672738.

Subtracting 66557 from its reverse (75566), we obtain a palindrome (9009).

The spelling of 66557 in words is "sixty-six thousand, five hundred fifty-seven".