641491136 has 112 divisors (see below), whose sum is σ = 1547713440. Its totient is φ = 259768320.

The previous prime is 641491133. The next prime is 641491159. The reversal of 641491136 is 631194146.

It is a junction number, because it is equal to n+sod(n) for n = 641491096 and 641491105.

It is not an unprimeable number, because it can be changed into a prime (641491133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 264200 + ... + 266616.

It is an arithmetic number, because the mean of its divisors is an integer number (13818870).

Almost surely, 2^641491136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641491136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (773856720).

641491136 is an abundant number, since it is smaller than the sum of its proper divisors (906222304).

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

641491136 is a wasteful number, since it uses less digits than its factorization.

641491136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2482 (or 2472 counting only the distinct ones).

The product of its digits is 15552, while the sum is 35.

The square root of 641491136 is about 25327.6752979819. The cubic root of 641491136 is about 862.4426392155.

The spelling of 641491136 in words is "six hundred forty-one million, four hundred ninety-one thousand, one hundred thirty-six".