66666967 has 4 divisors (see below), whose sum is σ = 67005576. Its totient is φ = 66328360.

The previous prime is 66666937. The next prime is 66666973. The reversal of 66666967 is 76966666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66666967 - 2¹¹ = 66664919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66666937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169009 + ... + 169402.

It is an arithmetic number, because the mean of its divisors is an integer number (16751394).

Almost surely, 2^66666967 is an apocalyptic number.

66666967 is a deficient number, since it is larger than the sum of its proper divisors (338609).

66666967 is a wasteful number, since it uses less digits than its factorization.

66666967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338608.

The product of its digits is 2939328, while the sum is 52.

The square root of 66666967 is about 8164.9842008420. The cubic root of 66666967 is about 405.4807419333.

The spelling of 66666967 in words is "sixty-six million, six hundred sixty-six thousand, nine hundred sixty-seven".