667210639 has 2 divisors, whose sum is σ = 667210640. Its totient is φ = 667210638.

The previous prime is 667210597. The next prime is 667210651. The reversal of 667210639 is 936012766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 667210639 - 2¹³ = 667202447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667210699) 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, 333605319 + 333605320.

It is an arithmetic number, because the mean of its divisors is an integer number (333605320).

Almost surely, 2^667210639 is an apocalyptic number.

667210639 is a deficient number, since it is larger than the sum of its proper divisors (1).

667210639 is an equidigital number, since it uses as much as digits as its factorization.

667210639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81648, while the sum is 40.

The square root of 667210639 is about 25830.4208057089. The cubic root of 667210639 is about 873.8180019431.

The spelling of 667210639 in words is "six hundred sixty-seven million, two hundred ten thousand, six hundred thirty-nine".