641240 has 64 divisors (see below), whose sum is σ = 1632960. Its totient is φ = 225280.

The previous prime is 641239. The next prime is 641261. The reversal of 641240 is 42146.

641240 = 47² + 48² + ... + 126².

It is a super-2 number, since 2×641240² = 822377475200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15620 + ... + 15660.

It is an arithmetic number, because the mean of its divisors is an integer number (25515).

2⁶⁴¹²⁴⁰ 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 641240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (816480).

641240 is an abundant number, since it is smaller than the sum of its proper divisors (991720).

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

641240 is a wasteful number, since it uses less digits than its factorization.

641240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 641240 is about 800.7746249726. The cubic root of 641240 is about 86.2330079248.

Adding to 641240 its reverse (42146), we get a palindrome (683386).

The spelling of 641240 in words is "six hundred forty-one thousand, two hundred forty".