640612267 has 2 divisors, whose sum is σ = 640612268. Its totient is φ = 640612266.

The previous prime is 640612213. The next prime is 640612277. The reversal of 640612267 is 762216046.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640612267 is a prime.

It is not a weakly prime, because it can be changed into another prime (640612277) 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 as a sum of consecutive naturals, namely, 320306133 + 320306134.

It is an arithmetic number, because the mean of its divisors is an integer number (320306134).

Almost surely, 2^640612267 is an apocalyptic number.

640612267 is a deficient number, since it is larger than the sum of its proper divisors (1).

640612267 is an equidigital number, since it uses as much as digits as its factorization.

640612267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 640612267 is about 25310.3193776768. The cubic root of 640612267 is about 862.0485986887.

The spelling of 640612267 in words is "six hundred forty million, six hundred twelve thousand, two hundred sixty-seven".