646646642 has 32 divisors (see below), whose sum is σ = 1013031360. Its totient is φ = 309355200.

The previous prime is 646646641. The next prime is 646646653. The reversal of 646646642 is 246646646.

It is a junction number, because it is equal to n+sod(n) for n = 646646593 and 646646602.

It is not an unprimeable number, because it can be changed into a prime (646646641) 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, 946433 + ... + 947115.

It is an arithmetic number, because the mean of its divisors is an integer number (31657230).

Almost surely, 2^646646642 is an apocalyptic number.

646646642 is a deficient number, since it is larger than the sum of its proper divisors (366384718).

646646642 is a wasteful number, since it uses less digits than its factorization.

646646642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 938.

The product of its digits is 995328, while the sum is 44.

The square root of 646646642 is about 25429.2477670890. The cubic root of 646646642 is about 864.7468902040.

The spelling of 646646642 in words is "six hundred forty-six million, six hundred forty-six thousand, six hundred forty-two".