641642906 has 8 divisors (see below), whose sum is σ = 966016704. Its totient is φ = 319637340.

The previous prime is 641642899. The next prime is 641642909. The reversal of 641642906 is 609246146.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 641642906.

It is not an unprimeable number, because it can be changed into a prime (641642909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 591380 + ... + 592463.

It is an arithmetic number, because the mean of its divisors is an integer number (120752088).

Almost surely, 2^641642906 is an apocalyptic number.

641642906 is a deficient number, since it is larger than the sum of its proper divisors (324373798).

641642906 is a wasteful number, since it uses less digits than its factorization.

641642906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1184116.

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 641642906 is about 25330.6712504821. The cubic root of 641642906 is about 862.5106487798.

The spelling of 641642906 in words is "six hundred forty-one million, six hundred forty-two thousand, nine hundred six".