667072217 has 4 divisors (see below), whose sum is σ = 762368256. Its totient is φ = 571776180.

The previous prime is 667072213. The next prime is 667072253. The reversal of 667072217 is 712270766.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 667072217 - 2² = 667072213 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667072213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47648009 + ... + 47648022.

It is an arithmetic number, because the mean of its divisors is an integer number (190592064).

Almost surely, 2^667072217 is an apocalyptic number.

It is an amenable number.

667072217 is a deficient number, since it is larger than the sum of its proper divisors (95296039).

667072217 is an equidigital number, since it uses as much as digits as its factorization.

667072217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95296038.

The product of its (nonzero) digits is 49392, while the sum is 38.

The square root of 667072217 is about 25827.7412291513. The cubic root of 667072217 is about 873.7575692531.

It can be divided in two parts, 6670 and 72217, that added together give a palindrome (78887).

The spelling of 667072217 in words is "six hundred sixty-seven million, seventy-two thousand, two hundred seventeen".