667217407 has 2 divisors, whose sum is σ = 667217408. Its totient is φ = 667217406.

The previous prime is 667217401. The next prime is 667217431. The reversal of 667217407 is 704712766.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 667217407 - 2³ = 667217399 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 667217407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667217401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333608703 + 333608704.

It is an arithmetic number, because the mean of its divisors is an integer number (333608704).

Almost surely, 2^667217407 is an apocalyptic number.

667217407 is a deficient number, since it is larger than the sum of its proper divisors (1).

667217407 is an equidigital number, since it uses as much as digits as its factorization.

667217407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 98784, while the sum is 40.

The square root of 667217407 is about 25830.5518136953. The cubic root of 667217407 is about 873.8209565224.

The spelling of 667217407 in words is "six hundred sixty-seven million, two hundred seventeen thousand, four hundred seven".