641605984 has 96 divisors (see below), whose sum is σ = 1371686400. Its totient is φ = 294497280.

The previous prime is 641605981. The next prime is 641606033. The reversal of 641605984 is 489506146.

It is a self number, because there is not a number n which added to its sum of digits gives 641605984.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641605981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3841869 + ... + 3842035.

It is an arithmetic number, because the mean of its divisors is an integer number (14288400).

Almost surely, 2^641605984 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 641605984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (685843200).

641605984 is an abundant number, since it is smaller than the sum of its proper divisors (730080416).

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

641605984 is a wasteful number, since it uses less digits than its factorization.

641605984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356 (or 348 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 43.

The square root of 641605984 is about 25329.9424397293. The cubic root of 641605984 is about 862.4941046716.

The spelling of 641605984 in words is "six hundred forty-one million, six hundred five thousand, nine hundred eighty-four".