646646605 has 16 divisors (see below), whose sum is σ = 849429504. Its totient is φ = 468671680.

The previous prime is 646646603. The next prime is 646646617. The reversal of 646646605 is 506646646.

It is not a de Polignac number, because 646646605 - 2¹ = 646646603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646646603) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3949 + ... + 36178.

It is an arithmetic number, because the mean of its divisors is an integer number (53089344).

Almost surely, 2^646646605 is an apocalyptic number.

It is an amenable number.

646646605 is a deficient number, since it is larger than the sum of its proper divisors (202782899).

646646605 is a wasteful number, since it uses less digits than its factorization.

646646605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40436.

The product of its (nonzero) digits is 622080, while the sum is 43.

The square root of 646646605 is about 25429.2470395802. The cubic root of 646646605 is about 864.7468737109.

The spelling of 646646605 in words is "six hundred forty-six million, six hundred forty-six thousand, six hundred five".