641280 has 72 divisors (see below), whose sum is σ = 2060352. Its totient is φ = 169984.

The previous prime is 641279. The next prime is 641287. The reversal of 641280 is 82146.

It is a super-2 number, since 2×641280² = 822480076800, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (641287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3757 + ... + 3923.

It is an arithmetic number, because the mean of its divisors is an integer number (28616).

2⁶⁴¹²⁸⁰ is an apocalyptic number.

641280 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1030176).

641280 is an abundant number, since it is smaller than the sum of its proper divisors (1419072).

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

641280 is a wasteful number, since it uses less digits than its factorization.

641280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 641280 is about 800.7996003995. The cubic root of 641280 is about 86.2348009344.

The spelling of 641280 in words is "six hundred forty-one thousand, two hundred eighty".