647644106 has 4 divisors (see below), whose sum is σ = 971466162. Its totient is φ = 323822052.

The previous prime is 647644091. The next prime is 647644139. The reversal of 647644106 is 601446746.

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

It can be written as a sum of positive squares in only one way, i.e., 644702881 + 2941225 = 25391^2 + 1715^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 647644106.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161911025 + ... + 161911028.

Almost surely, 2^647644106 is an apocalyptic number.

647644106 is a deficient number, since it is larger than the sum of its proper divisors (323822056).

647644106 is a wasteful number, since it uses less digits than its factorization.

647644106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323822055.

The product of its (nonzero) digits is 96768, while the sum is 38.

The square root of 647644106 is about 25448.8527442791. The cubic root of 647644106 is about 865.1912909602.

The spelling of 647644106 in words is "six hundred forty-seven million, six hundred forty-four thousand, one hundred six".