641940 has 48 divisors (see below), whose sum is σ = 1938048. Its totient is φ = 157824.

The previous prime is 641929. The next prime is 641959. The reversal of 641940 is 49146.

641940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 641940.

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, 369 + ... + 1191.

It is an arithmetic number, because the mean of its divisors is an integer number (40376).

2⁶⁴¹⁹⁴⁰ is an apocalyptic number.

641940 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 641940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (969024).

641940 is an abundant number, since it is smaller than the sum of its proper divisors (1296108).

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

641940 is a wasteful number, since it uses less digits than its factorization.

641940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848 (or 846 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 641940 is about 801.2115825423. The cubic root of 641940 is about 86.2643748358.

The spelling of 641940 in words is "six hundred forty-one thousand, nine hundred forty".