66665967 has 8 divisors (see below), whose sum is σ = 90013440. Its totient is φ = 43881240.

The previous prime is 66665957. The next prime is 66666007. The reversal of 66665967 is 76956666.

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

It is a de Polignac number, because none of the positive numbers 2^k-66665967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66665957) 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, 140409 + ... + 140882.

It is an arithmetic number, because the mean of its divisors is an integer number (11251680).

Almost surely, 2^66665967 is an apocalyptic number.

66665967 is a deficient number, since it is larger than the sum of its proper divisors (23347473).

66665967 is a wasteful number, since it uses less digits than its factorization.

66665967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281373.

The product of its digits is 2449440, while the sum is 51.

The square root of 66665967 is about 8164.9229635068. The cubic root of 66665967 is about 405.4787145286.

The spelling of 66665967 in words is "sixty-six million, six hundred sixty-five thousand, nine hundred sixty-seven".