642606646 has 16 divisors (see below), whose sum is σ = 1052725248. Its totient is φ = 291764200.

The previous prime is 642606641. The next prime is 642606659. The reversal of 642606646 is 646606246.

642606646 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 642606599 and 642606608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642606641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4011 + ... + 36073.

It is an arithmetic number, because the mean of its divisors is an integer number (65795328).

Almost surely, 2^642606646 is an apocalyptic number.

642606646 is a deficient number, since it is larger than the sum of its proper divisors (410118602).

642606646 is a wasteful number, since it uses less digits than its factorization.

642606646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32987.

The product of its (nonzero) digits is 248832, while the sum is 40.

The square root of 642606646 is about 25349.6872959017. The cubic root of 642606646 is about 862.9422596665.

The spelling of 642606646 in words is "six hundred forty-two million, six hundred six thousand, six hundred forty-six".