66417321 has 8 divisors (see below), whose sum is σ = 90227520. Its totient is φ = 43442672.

The previous prime is 66417277. The next prime is 66417341. The reversal of 66417321 is 12371466.

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 66417321 - 2⁷ = 66417193 is a prime.

It is a super-2 number, since 2×66417321² = 8822521057634082, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66417341) 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, 208701 + ... + 209018.

It is an arithmetic number, because the mean of its divisors is an integer number (11278440).

Almost surely, 2^66417321 is an apocalyptic number.

It is an amenable number.

66417321 is a deficient number, since it is larger than the sum of its proper divisors (23810199).

66417321 is a wasteful number, since it uses less digits than its factorization.

66417321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417775.

The product of its digits is 6048, while the sum is 30.

The square root of 66417321 is about 8149.6822637450. The cubic root of 66417321 is about 404.9739779043.

Adding to 66417321 its reverse (12371466), we get a palindrome (78788787).

The spelling of 66417321 in words is "sixty-six million, four hundred seventeen thousand, three hundred twenty-one".