647642267 has 4 divisors (see below), whose sum is σ = 653930160. Its totient is φ = 641354376.

The previous prime is 647642249. The next prime is 647642279. The reversal of 647642267 is 762246746.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647642267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (647642207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3143792 + ... + 3143997.

It is an arithmetic number, because the mean of its divisors is an integer number (163482540).

Almost surely, 2^647642267 is an apocalyptic number.

647642267 is a deficient number, since it is larger than the sum of its proper divisors (6287893).

647642267 is a wasteful number, since it uses less digits than its factorization.

647642267 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6287892.

The product of its digits is 677376, while the sum is 44.

The square root of 647642267 is about 25448.8166129586. The cubic root of 647642267 is about 865.1904720494.

The spelling of 647642267 in words is "six hundred forty-seven million, six hundred forty-two thousand, two hundred sixty-seven".