66616617 has 8 divisors (see below), whose sum is σ = 89029024. Its totient is φ = 44307648.

The previous prime is 66616609. The next prime is 66616621. The reversal of 66616617 is 71661666.

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

It is not a de Polignac number, because 66616617 - 2³ = 66616609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66616657) 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, 24343 + ... + 26940.

It is an arithmetic number, because the mean of its divisors is an integer number (11128628).

Almost surely, 2^66616617 is an apocalyptic number.

It is an amenable number.

66616617 is a deficient number, since it is larger than the sum of its proper divisors (22412407).

66616617 is a wasteful number, since it uses less digits than its factorization.

66616617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51719.

The product of its digits is 54432, while the sum is 39.

The square root of 66616617 is about 8161.9003301927. The cubic root of 66616617 is about 405.3786369073.

The spelling of 66616617 in words is "sixty-six million, six hundred sixteen thousand, six hundred seventeen".