66667667 has 8 divisors (see below), whose sum is σ = 74276352. Its totient is φ = 59317000.

The previous prime is 66667649. The next prime is 66667691. The reversal of 66667667 is 76676666.

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 66667667 - 2¹⁰ = 66666643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66667697) 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, 63959 + ... + 64992.

It is an arithmetic number, because the mean of its divisors is an integer number (9284544).

Almost surely, 2^66667667 is an apocalyptic number.

66667667 is a deficient number, since it is larger than the sum of its proper divisors (7608685).

66667667 is a wasteful number, since it uses less digits than its factorization.

66667667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129009.

The product of its digits is 2286144, while the sum is 50.

The square root of 66667667 is about 8165.0270667035. The cubic root of 66667667 is about 405.4821611045.

The spelling of 66667667 in words is "sixty-six million, six hundred sixty-seven thousand, six hundred sixty-seven".