641364640 has 96 divisors (see below), whose sum is σ = 1774047744. Its totient is φ = 214517760.

The previous prime is 641364617. The next prime is 641364649. The reversal of 641364640 is 46463146.

It is a super-2 number, since 2×641364640² = 822697202884659200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 641364596 and 641364605.

It is not an unprimeable number, because it can be changed into a prime (641364649) 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 15 ways as a sum of consecutive naturals, for example, 38937 + ... + 52903.

It is an arithmetic number, because the mean of its divisors is an integer number (18479664).

Almost surely, 2^641364640 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 641364640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (887023872).

641364640 is an abundant number, since it is smaller than the sum of its proper divisors (1132683104).

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

641364640 is a wasteful number, since it uses less digits than its factorization.

641364640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14030 (or 14022 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 34.

The square root of 641364640 is about 25325.1779855542. The cubic root of 641364640 is about 862.3859469716.

The spelling of 641364640 in words is "six hundred forty-one million, three hundred sixty-four thousand, six hundred forty".