667216511 has 4 divisors (see below), whose sum is σ = 718540872. Its totient is φ = 615892152.

The previous prime is 667216469. The next prime is 667216513. The reversal of 667216511 is 115612766.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667216511 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 (667216513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25662161 + ... + 25662186.

It is an arithmetic number, because the mean of its divisors is an integer number (179635218).

Almost surely, 2^667216511 is an apocalyptic number.

667216511 is a deficient number, since it is larger than the sum of its proper divisors (51324361).

667216511 is a wasteful number, since it uses less digits than its factorization.

667216511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51324360.

The product of its digits is 15120, while the sum is 35.

The square root of 667216511 is about 25830.5344698866. The cubic root of 667216511 is about 873.8205653735.

The spelling of 667216511 in words is "six hundred sixty-seven million, two hundred sixteen thousand, five hundred eleven".