645646426266 has 8 divisors (see below), whose sum is σ = 1291292852544. Its totient is φ = 215215475420.

The previous prime is 645646426219. The next prime is 645646426291. The reversal of 645646426266 is 662624646546.

It is a sphenic number, since it is the product of 3 distinct primes.

645646426266 is an admirable number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 53803868850 + ... + 53803868861.

It is an arithmetic number, because the mean of its divisors is an integer number (161411606568).

Almost surely, 2^645646426266 is an apocalyptic number.

645646426266 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645646426266 is a wasteful number, since it uses less digits than its factorization.

645646426266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107607737716.

The product of its digits is 59719680, while the sum is 57.

The spelling of 645646426266 in words is "six hundred forty-five billion, six hundred forty-six million, four hundred twenty-six thousand, two hundred sixty-six".