641087440 has 80 divisors (see below), whose sum is σ = 1758458880. Its totient is φ = 212705280.

The previous prime is 641087431. The next prime is 641087443. The reversal of 641087440 is 44780146.

641087440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 641087396 and 641087405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641087443) 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, 1105 + ... + 35824.

It is an arithmetic number, because the mean of its divisors is an integer number (21980736).

Almost surely, 2^641087440 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 641087440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (879229440).

641087440 is an abundant number, since it is smaller than the sum of its proper divisors (1117371440).

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

641087440 is a wasteful number, since it uses less digits than its factorization.

641087440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36980 (or 36974 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 641087440 is about 25319.7045796352. The cubic root of 641087440 is about 862.2616870121.

The spelling of 641087440 in words is "six hundred forty-one million, eighty-seven thousand, four hundred forty".