641906568 has 48 divisors (see below), whose sum is σ = 1740199500. Its totient is φ = 213759360.

The previous prime is 641906549. The next prime is 641906569. The reversal of 641906568 is 865609146.

It can be written as a sum of positive squares in 2 ways, for example, as 530012484 + 111894084 = 23022^2 + 10578^2 .

It is not an unprimeable number, because it can be changed into a prime (641906569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81258 + ... + 88806.

Almost surely, 2^641906568 is an apocalyptic number.

It is an amenable number.

641906568 is an abundant number, since it is smaller than the sum of its proper divisors (1098292932).

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

641906568 is a wasteful number, since it uses less digits than its factorization.

641906568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8742 (or 8735 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 641906568 is about 25335.8751181008. The cubic root of 641906568 is about 862.6287727075.

The spelling of 641906568 in words is "six hundred forty-one million, nine hundred six thousand, five hundred sixty-eight".