66205281 has 8 divisors (see below), whose sum is σ = 90152064. Its totient is φ = 43197680.

The previous prime is 66205277. The next prime is 66205301. The reversal of 66205281 is 18250266.

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 66205281 - 2² = 66205277 is a prime.

It is a super-2 number, since 2×66205281² = 8766278464577922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66205211) 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, 234630 + ... + 234911.

It is an arithmetic number, because the mean of its divisors is an integer number (11269008).

Almost surely, 2^66205281 is an apocalyptic number.

It is an amenable number.

66205281 is a deficient number, since it is larger than the sum of its proper divisors (23946783).

66205281 is a wasteful number, since it uses less digits than its factorization.

66205281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469591.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 66205281 is about 8136.6627679903. The cubic root of 66205281 is about 404.5425531631.

The spelling of 66205281 in words is "sixty-six million, two hundred five thousand, two hundred eighty-one".