667211407 has 2 divisors, whose sum is σ = 667211408. Its totient is φ = 667211406.

The previous prime is 667211401. The next prime is 667211411. The reversal of 667211407 is 704112766.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667211407 - 2¹⁵ = 667178639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667211401) 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 as a sum of consecutive naturals, namely, 333605703 + 333605704.

It is an arithmetic number, because the mean of its divisors is an integer number (333605704).

Almost surely, 2^667211407 is an apocalyptic number.

667211407 is a deficient number, since it is larger than the sum of its proper divisors (1).

667211407 is an equidigital number, since it uses as much as digits as its factorization.

667211407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 667211407 is about 25830.4356718968. The cubic root of 667211407 is about 873.8183372155.

The spelling of 667211407 in words is "six hundred sixty-seven million, two hundred eleven thousand, four hundred seven".