66966665 has 8 divisors (see below), whose sum is σ = 82952448. Its totient is φ = 51845040.

The previous prime is 66966661. The next prime is 66966673. The reversal of 66966665 is 56666966.

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

It is not a de Polignac number, because 66966665 - 2² = 66966661 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66966661) 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, 215867 + ... + 216176.

It is an arithmetic number, because the mean of its divisors is an integer number (10369056).

Almost surely, 2^66966665 is an apocalyptic number.

It is an amenable number.

66966665 is a deficient number, since it is larger than the sum of its proper divisors (15985783).

66966665 is a wasteful number, since it uses less digits than its factorization.

66966665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432079.

The product of its digits is 2099520, while the sum is 50.

The square root of 66966665 is about 8183.3162593169. The cubic root of 66966665 is about 406.0874398126.

The spelling of 66966665 in words is "sixty-six million, nine hundred sixty-six thousand, six hundred sixty-five".